MC

322c_df37

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 7 offspring, which expression gives the probability of exactly 3 brown and 4 black, in any order?

⟮  7  ⟯
3
(¼)4⋅(¾)3=
7!
(7–3)! ⋅ 3!
(¼)4⋅(¾)3=
7⋅6⋅5
3⋅2
×
14 ⋅ 33
44 ⋅ 43
=
35 × 27
16384
=0.0577 = 5.8%
Incorrect
⟮  7  ⟯
3
×(1/4)3=0.5469 = 54.7%
Incorrect
⟮  4  ⟯
4
(¼)0⋅(¾)4=
4!
(4–4)! ⋅ 4!
(¼)0⋅(¾)4=
1
1
×
10 ⋅ 34
40 ⋅ 44
=
1 × 81
256
=0.3164 = 31.6%
Incorrect
⟮  7  ⟯
3
(¾)4⋅(¼)3=
7!
(7–3)! ⋅ 3!
(¾)4⋅(¼)3=
7⋅6⋅5
3⋅2
×
34 ⋅ 13
44 ⋅ 43
=
35 × 81
16384
=0.1730 = 17.3%
Correct MC

832f_948a

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 9 surviving offspring, which expression gives the probability of exactly 4 short-tailed and 5 long-tailed, in any order?

⟮  5  ⟯
5
(⅓)0⋅(⅔)5=
5!
(5–5)! ⋅ 5!
(⅓)0⋅(⅔)5=
1
1
×
10 ⋅ 25
30 ⋅ 35
=
1 × 32
243
=0.1317 = 13.2%
Incorrect
⟮  9  ⟯
4
(⅓)5⋅(⅔)4=
9!
(9–4)! ⋅ 4!
(⅓)5⋅(⅔)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 24
35 ⋅ 34
=
126 × 16
19683
=0.1024 = 10.2%
Correct
⟮  5  ⟯
4
(⅓)1⋅(⅔)4=
5!
(5–4)! ⋅ 4!
(⅓)1⋅(⅔)4=
5
1
×
11 ⋅ 24
31 ⋅ 34
=
5 × 16
243
=0.3292 = 32.9%
Incorrect
⟮  9  ⟯
5
(⅓)4⋅(⅔)5=
9!
(9–5)! ⋅ 5!
(⅓)4⋅(⅔)5=
9⋅8⋅7⋅6
4⋅3⋅2
×
14 ⋅ 25
34 ⋅ 35
=
126 × 32
19683
=0.2048 = 20.5%
Incorrect MC

a1a4_23dd

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 5 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 3 long-tailed, in any order?

⟮  5  ⟯
2
(⅓)3⋅(⅔)2=
5!
(5–2)! ⋅ 2!
(⅓)3⋅(⅔)2=
5⋅4
2
×
13 ⋅ 22
33 ⋅ 32
=
10 × 4
243
=0.1646 = 16.5%
Correct
⟮  3  ⟯
3
(⅓)0⋅(⅔)3=
3!
(3–3)! ⋅ 3!
(⅓)0⋅(⅔)3=
1
1
×
10 ⋅ 23
30 ⋅ 33
=
1 × 8
27
=0.2963 = 29.6%
Incorrect
⟮  2  ⟯
2
(⅔)0⋅(⅓)2=
2!
(2–2)! ⋅ 2!
(⅔)0⋅(⅓)2=
1
1
×
20 ⋅ 12
30 ⋅ 32
=
1
9
=0.1111 = 11.1%
Incorrect
⟮  5  ⟯
2
(⅔)3⋅(⅓)2=
5!
(5–2)! ⋅ 2!
(⅔)3⋅(⅓)2=
5⋅4
2
×
23 ⋅ 12
33 ⋅ 32
=
10 × 8
243
=0.3292 = 32.9%
Incorrect MC

75c0_25ca

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 6 offspring, which expression gives the probability of exactly 2 purple and 4 white, in any order?

⟮  4  ⟯
2
(¾)2⋅(¼)2=
4!
(4–2)! ⋅ 2!
(¾)2⋅(¼)2=
4⋅3
2
×
32 ⋅ 12
42 ⋅ 42
=
6 × 9
256
=0.2109 = 21.1%
Incorrect
⟮  4  ⟯
4
(¼)0⋅(¾)4=
4!
(4–4)! ⋅ 4!
(¼)0⋅(¾)4=
1
1
×
10 ⋅ 34
40 ⋅ 44
=
1 × 81
256
=0.3164 = 31.6%
Incorrect
⟮  6  ⟯
2
(¼)4⋅(¾)2=
6!
(6–2)! ⋅ 2!
(¼)4⋅(¾)2=
6⋅5
2
×
14 ⋅ 32
44 ⋅ 42
=
15 × 9
4096
=0.0330 = 3.3%
Correct
⟮  6  ⟯
4
(¼)2⋅(¾)4=
6!
(6–4)! ⋅ 4!
(¼)2⋅(¾)4=
6⋅5
2
×
12 ⋅ 34
42 ⋅ 44
=
15 × 81
4096
=0.2966 = 29.7%
Incorrect MC

832f_11fe

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 9 surviving offspring, which expression gives the probability of exactly 4 short-tailed and 5 long-tailed, in any order?

⟮  4  ⟯
4
(⅔)0⋅(⅓)4=
4!
(4–4)! ⋅ 4!
(⅔)0⋅(⅓)4=
1
1
×
20 ⋅ 14
30 ⋅ 34
=
1
81
=0.0123 = 1.2%
Incorrect
⟮  9  ⟯
4
(⅓)5⋅(⅔)4=
9!
(9–4)! ⋅ 4!
(⅓)5⋅(⅔)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 24
35 ⋅ 34
=
126 × 16
19683
=0.1024 = 10.2%
Correct
⟮  5  ⟯
4
(⅔)1⋅(⅓)4=
5!
(5–4)! ⋅ 4!
(⅔)1⋅(⅓)4=
5
1
×
21 ⋅ 14
31 ⋅ 34
=
5 × 2
243
=0.0412 = 4.1%
Incorrect
⟮  9  ⟯
4
(⅔)5⋅(⅓)4=
9!
(9–4)! ⋅ 4!
(⅔)5⋅(⅓)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
25 ⋅ 14
35 ⋅ 34
=
126 × 32
19683
=0.2048 = 20.5%
Incorrect MC

e0f0_497b

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 6 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 4 long-tailed, in any order?

⟮  6  ⟯
2
(⅓)4⋅(⅔)2=
6!
(6–2)! ⋅ 2!
(⅓)4⋅(⅔)2=
6⋅5
2
×
14 ⋅ 22
34 ⋅ 32
=
15 × 4
729
=0.0823 = 8.2%
Correct
⟮  4  ⟯
4
(⅓)0⋅(⅔)4=
4!
(4–4)! ⋅ 4!
(⅓)0⋅(⅔)4=
1
1
×
10 ⋅ 24
30 ⋅ 34
=
1 × 16
81
=0.1975 = 19.8%
Incorrect
⟮  6  ⟯
2
(⅔)4⋅(⅓)2=
6!
(6–2)! ⋅ 2!
(⅔)4⋅(⅓)2=
6⋅5
2
×
24 ⋅ 12
34 ⋅ 32
=
15 × 16
729
=0.3292 = 32.9%
Incorrect
⟮  6  ⟯
6
(⅓)0⋅(⅔)6=
6!
(6–6)! ⋅ 6!
(⅓)0⋅(⅔)6=
1
1
×
10 ⋅ 26
30 ⋅ 36
=
1 × 64
729
=0.0878 = 8.8%
Incorrect MC

a1a4_7628

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 5 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 3 long-tailed, in any order?

⟮  3  ⟯
2
(⅔)1⋅(⅓)2=
3!
(3–2)! ⋅ 2!
(⅔)1⋅(⅓)2=
3
1
×
21 ⋅ 12
31 ⋅ 32
=
3 × 2
27
=0.2222 = 22.2%
Incorrect
⟮  2  ⟯
2
(⅔)0⋅(⅓)2=
2!
(2–2)! ⋅ 2!
(⅔)0⋅(⅓)2=
1
1
×
20 ⋅ 12
30 ⋅ 32
=
1
9
=0.1111 = 11.1%
Incorrect
⟮  5  ⟯
2
(⅓)3⋅(⅔)2=
5!
(5–2)! ⋅ 2!
(⅓)3⋅(⅔)2=
5⋅4
2
×
13 ⋅ 22
33 ⋅ 32
=
10 × 4
243
=0.1646 = 16.5%
Correct
⟮  5  ⟯
2
(⅔)3⋅(⅓)2=
5!
(5–2)! ⋅ 2!
(⅔)3⋅(⅓)2=
5⋅4
2
×
23 ⋅ 12
33 ⋅ 32
=
10 × 8
243
=0.3292 = 32.9%
Incorrect MC

b71d_e5ee

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 9 offspring, which expression gives the probability of exactly 4 purple and 5 white, in any order?

⟮  9  ⟯
4
(¼)5⋅(¾)4=
9!
(9–4)! ⋅ 4!
(¼)5⋅(¾)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 34
45 ⋅ 44
=
126 × 81
262144
=0.0389 = 3.9%
Correct
⟮  5  ⟯
4
(¾)1⋅(¼)4=
5!
(5–4)! ⋅ 4!
(¾)1⋅(¼)4=
5
1
×
31 ⋅ 14
41 ⋅ 44
=
5 × 3
1024
=0.0146 = 1.5%
Incorrect
⟮  5  ⟯
5
(¼)0⋅(¾)5=
5!
(5–5)! ⋅ 5!
(¼)0⋅(¾)5=
1
1
×
10 ⋅ 35
40 ⋅ 45
=
1 × 243
1024
=0.2373 = 23.7%
Incorrect
⟮  4  ⟯
4
(¼)0⋅(¾)4=
4!
(4–4)! ⋅ 4!
(¼)0⋅(¾)4=
1
1
×
10 ⋅ 34
40 ⋅ 44
=
1 × 81
256
=0.3164 = 31.6%
Incorrect MC

75c0_d3ef

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 6 offspring, which expression gives the probability of exactly 2 purple and 4 white, in any order?

⟮  6  ⟯
6
(¼)0⋅(¾)6=
6!
(6–6)! ⋅ 6!
(¼)0⋅(¾)6=
1
1
×
10 ⋅ 36
40 ⋅ 46
=
1 × 729
4096
=0.1780 = 17.8%
Incorrect
⟮  2  ⟯
2
(¼)0⋅(¾)2=
2!
(2–2)! ⋅ 2!
(¼)0⋅(¾)2=
1
1
×
10 ⋅ 32
40 ⋅ 42
=
1 × 9
16
=0.5625 = 56.2%
Incorrect
⟮  6  ⟯
4
(¼)2⋅(¾)4=
6!
(6–4)! ⋅ 4!
(¼)2⋅(¾)4=
6⋅5
2
×
12 ⋅ 34
42 ⋅ 44
=
15 × 81
4096
=0.2966 = 29.7%
Incorrect
⟮  6  ⟯
2
(¼)4⋅(¾)2=
6!
(6–2)! ⋅ 2!
(¼)4⋅(¾)2=
6⋅5
2
×
14 ⋅ 32
44 ⋅ 42
=
15 × 9
4096
=0.0330 = 3.3%
Correct MC

a1a4_cc30

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 5 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 3 long-tailed, in any order?

⟮  5  ⟯
2
(⅔)3⋅(⅓)2=
5!
(5–2)! ⋅ 2!
(⅔)3⋅(⅓)2=
5⋅4
2
×
23 ⋅ 12
33 ⋅ 32
=
10 × 8
243
=0.3292 = 32.9%
Incorrect
(2/3)2 × (1/3)3=0.0165 = 1.6%
Incorrect
⟮  5  ⟯
2
(⅓)3⋅(⅔)2=
5!
(5–2)! ⋅ 2!
(⅓)3⋅(⅔)2=
5⋅4
2
×
13 ⋅ 22
33 ⋅ 32
=
10 × 4
243
=0.1646 = 16.5%
Correct
⟮  3  ⟯
3
(⅔)0⋅(⅓)3=
3!
(3–3)! ⋅ 3!
(⅔)0⋅(⅓)3=
1
1
×
20 ⋅ 13
30 ⋅ 33
=
1
27
=0.0370 = 3.7%
Incorrect MC

2923_d9ba

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 8 surviving offspring, which expression gives the probability of exactly 3 short-tailed and 5 long-tailed, in any order?

⟮  3  ⟯
3
(⅔)0⋅(⅓)3=
3!
(3–3)! ⋅ 3!
(⅔)0⋅(⅓)3=
1
1
×
20 ⋅ 13
30 ⋅ 33
=
1
27
=0.0370 = 3.7%
Incorrect
⟮  8  ⟯
3
(⅔)5⋅(⅓)3=
8!
(8–3)! ⋅ 3!
(⅔)5⋅(⅓)3=
8⋅7⋅6
3⋅2
×
25 ⋅ 13
35 ⋅ 33
=
56 × 32
6561
=0.2731 = 27.3%
Incorrect
⟮  8  ⟯
3
(⅓)5⋅(⅔)3=
8!
(8–3)! ⋅ 3!
(⅓)5⋅(⅔)3=
8⋅7⋅6
3⋅2
×
15 ⋅ 23
35 ⋅ 33
=
56 × 8
6561
=0.0683 = 6.8%
Correct
⟮  5  ⟯
3
(⅓)2⋅(⅔)3=
5!
(5–3)! ⋅ 3!
(⅓)2⋅(⅔)3=
5⋅4
2
×
12 ⋅ 23
32 ⋅ 33
=
10 × 8
243
=0.3292 = 32.9%
Incorrect MC

e0f0_83a6

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 6 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 4 long-tailed, in any order?

⟮  6  ⟯
2
(⅓)4⋅(⅔)2=
6!
(6–2)! ⋅ 2!
(⅓)4⋅(⅔)2=
6⋅5
2
×
14 ⋅ 22
34 ⋅ 32
=
15 × 4
729
=0.0823 = 8.2%
Correct
⟮  6  ⟯
2
(⅔)4⋅(⅓)2=
6!
(6–2)! ⋅ 2!
(⅔)4⋅(⅓)2=
6⋅5
2
×
24 ⋅ 12
34 ⋅ 32
=
15 × 16
729
=0.3292 = 32.9%
Incorrect
⟮  4  ⟯
2
(⅓)2⋅(⅔)2=
4!
(4–2)! ⋅ 2!
(⅓)2⋅(⅔)2=
4⋅3
2
×
12 ⋅ 22
32 ⋅ 32
=
6 × 4
81
=0.2963 = 29.6%
Incorrect
⟮  2  ⟯
2
(⅔)0⋅(⅓)2=
2!
(2–2)! ⋅ 2!
(⅔)0⋅(⅓)2=
1
1
×
20 ⋅ 12
30 ⋅ 32
=
1
9
=0.1111 = 11.1%
Incorrect MC

75c0_36c8

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 6 offspring, which expression gives the probability of exactly 2 purple and 4 white, in any order?

⟮  6  ⟯
6
(¼)0⋅(¾)6=
6!
(6–6)! ⋅ 6!
(¼)0⋅(¾)6=
1
1
×
10 ⋅ 36
40 ⋅ 46
=
1 × 729
4096
=0.1780 = 17.8%
Incorrect
⟮  4  ⟯
2
(¾)2⋅(¼)2=
4!
(4–2)! ⋅ 2!
(¾)2⋅(¼)2=
4⋅3
2
×
32 ⋅ 12
42 ⋅ 42
=
6 × 9
256
=0.2109 = 21.1%
Incorrect
⟮  2  ⟯
2
(¾)0⋅(¼)2=
2!
(2–2)! ⋅ 2!
(¾)0⋅(¼)2=
1
1
×
30 ⋅ 12
40 ⋅ 42
=
1
16
=0.0625 = 6.2%
Incorrect
⟮  6  ⟯
2
(¼)4⋅(¾)2=
6!
(6–2)! ⋅ 2!
(¼)4⋅(¾)2=
6⋅5
2
×
14 ⋅ 32
44 ⋅ 42
=
15 × 9
4096
=0.0330 = 3.3%
Correct MC

75c0_d2b9

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 6 offspring, which expression gives the probability of exactly 2 purple and 4 white, in any order?

⟮  2  ⟯
2
(¼)0⋅(¾)2=
2!
(2–2)! ⋅ 2!
(¼)0⋅(¾)2=
1
1
×
10 ⋅ 32
40 ⋅ 42
=
1 × 9
16
=0.5625 = 56.2%
Incorrect
⟮  6  ⟯
2
(¾)4⋅(¼)2=
6!
(6–2)! ⋅ 2!
(¾)4⋅(¼)2=
6⋅5
2
×
34 ⋅ 12
44 ⋅ 42
=
15 × 81
4096
=0.2966 = 29.7%
Incorrect
⟮  6  ⟯
2
(¼)4⋅(¾)2=
6!
(6–2)! ⋅ 2!
(¼)4⋅(¾)2=
6⋅5
2
×
14 ⋅ 32
44 ⋅ 42
=
15 × 9
4096
=0.0330 = 3.3%
Correct
⟮  4  ⟯
4
(¼)0⋅(¾)4=
4!
(4–4)! ⋅ 4!
(¼)0⋅(¾)4=
1
1
×
10 ⋅ 34
40 ⋅ 44
=
1 × 81
256
=0.3164 = 31.6%
Incorrect MC

322c_3717

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 7 offspring, which expression gives the probability of exactly 3 brown and 4 black, in any order?

⟮  7  ⟯
3
(¾)4⋅(¼)3=
7!
(7–3)! ⋅ 3!
(¾)4⋅(¼)3=
7⋅6⋅5
3⋅2
×
34 ⋅ 13
44 ⋅ 43
=
35 × 81
16384
=0.1730 = 17.3%
Correct
⟮  3  ⟯
3
(¼)0⋅(¾)3=
3!
(3–3)! ⋅ 3!
(¼)0⋅(¾)3=
1
1
×
10 ⋅ 33
40 ⋅ 43
=
1 × 27
64
=0.4219 = 42.2%
Incorrect
⟮  7  ⟯
3
(¼)4⋅(¾)3=
7!
(7–3)! ⋅ 3!
(¼)4⋅(¾)3=
7⋅6⋅5
3⋅2
×
14 ⋅ 33
44 ⋅ 43
=
35 × 27
16384
=0.0577 = 5.8%
Incorrect
⟮  7  ⟯
3
×(1/4)3=0.5469 = 54.7%
Incorrect MC

cb40_f64e

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 5 offspring, which expression gives the probability of exactly 2 purple and 3 white, in any order?

⟮  5  ⟯
2
(¼)3⋅(¾)2=
5!
(5–2)! ⋅ 2!
(¼)3⋅(¾)2=
5⋅4
2
×
13 ⋅ 32
43 ⋅ 42
=
10 × 9
1024
=0.0879 = 8.8%
Correct
⟮  5  ⟯
3
(¼)2⋅(¾)3=
5!
(5–3)! ⋅ 3!
(¼)2⋅(¾)3=
5⋅4
2
×
12 ⋅ 33
42 ⋅ 43
=
10 × 27
1024
=0.2637 = 26.4%
Incorrect
⟮  2  ⟯
2
(¾)0⋅(¼)2=
2!
(2–2)! ⋅ 2!
(¾)0⋅(¼)2=
1
1
×
30 ⋅ 12
40 ⋅ 42
=
1
16
=0.0625 = 6.2%
Incorrect
(3/4)2 × (1/4)3=0.0088 = 0.9%
Incorrect MC

b71d_c605

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 9 offspring, which expression gives the probability of exactly 4 purple and 5 white, in any order?

⟮  9  ⟯
9
(¼)0⋅(¾)9=
9!
(9–9)! ⋅ 9!
(¼)0⋅(¾)9=
1
1
×
10 ⋅ 39
40 ⋅ 49
=
1 × 19683
262144
=0.0751 = 7.5%
Incorrect
⟮  5  ⟯
4
(¼)1⋅(¾)4=
5!
(5–4)! ⋅ 4!
(¼)1⋅(¾)4=
5
1
×
11 ⋅ 34
41 ⋅ 44
=
5 × 81
1024
=0.3955 = 39.6%
Incorrect
⟮  9  ⟯
4
(¼)5⋅(¾)4=
9!
(9–4)! ⋅ 4!
(¼)5⋅(¾)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 34
45 ⋅ 44
=
126 × 81
262144
=0.0389 = 3.9%
Correct
⟮  9  ⟯
4
(¾)5⋅(¼)4=
9!
(9–4)! ⋅ 4!
(¾)5⋅(¼)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
35 ⋅ 14
45 ⋅ 44
=
126 × 243
262144
=0.1168 = 11.7%
Incorrect MC

cb40_0e43

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 5 offspring, which expression gives the probability of exactly 2 purple and 3 white, in any order?

⟮  5  ⟯
3
(¼)2⋅(¾)3=
5!
(5–3)! ⋅ 3!
(¼)2⋅(¾)3=
5⋅4
2
×
12 ⋅ 33
42 ⋅ 43
=
10 × 27
1024
=0.2637 = 26.4%
Incorrect
⟮  3  ⟯
2
(¾)1⋅(¼)2=
3!
(3–2)! ⋅ 2!
(¾)1⋅(¼)2=
3
1
×
31 ⋅ 12
41 ⋅ 42
=
3 × 3
64
=0.1406 = 14.1%
Incorrect
⟮  3  ⟯
3
(¾)0⋅(¼)3=
3!
(3–3)! ⋅ 3!
(¾)0⋅(¼)3=
1
1
×
30 ⋅ 13
40 ⋅ 43
=
1
64
=0.0156 = 1.6%
Incorrect
⟮  5  ⟯
2
(¼)3⋅(¾)2=
5!
(5–2)! ⋅ 2!
(¼)3⋅(¾)2=
5⋅4
2
×
13 ⋅ 32
43 ⋅ 42
=
10 × 9
1024
=0.0879 = 8.8%
Correct MC

832f_4456

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 9 surviving offspring, which expression gives the probability of exactly 4 short-tailed and 5 long-tailed, in any order?

⟮  9  ⟯
5
(⅓)4⋅(⅔)5=
9!
(9–5)! ⋅ 5!
(⅓)4⋅(⅔)5=
9⋅8⋅7⋅6
4⋅3⋅2
×
14 ⋅ 25
34 ⋅ 35
=
126 × 32
19683
=0.2048 = 20.5%
Incorrect
⟮  4  ⟯
4
(⅓)0⋅(⅔)4=
4!
(4–4)! ⋅ 4!
(⅓)0⋅(⅔)4=
1
1
×
10 ⋅ 24
30 ⋅ 34
=
1 × 16
81
=0.1975 = 19.8%
Incorrect
⟮  9  ⟯
4
(⅓)5⋅(⅔)4=
9!
(9–4)! ⋅ 4!
(⅓)5⋅(⅔)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 24
35 ⋅ 34
=
126 × 16
19683
=0.1024 = 10.2%
Correct
⟮  4  ⟯
4
(⅔)0⋅(⅓)4=
4!
(4–4)! ⋅ 4!
(⅔)0⋅(⅓)4=
1
1
×
20 ⋅ 14
30 ⋅ 34
=
1
81
=0.0123 = 1.2%
Incorrect MC

322c_7083

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 7 offspring, which expression gives the probability of exactly 3 brown and 4 black, in any order?

⟮  3  ⟯
3
(¼)0⋅(¾)3=
3!
(3–3)! ⋅ 3!
(¼)0⋅(¾)3=
1
1
×
10 ⋅ 33
40 ⋅ 43
=
1 × 27
64
=0.4219 = 42.2%
Incorrect
⟮  4  ⟯
3
(¾)1⋅(¼)3=
4!
(4–3)! ⋅ 3!
(¾)1⋅(¼)3=
4
1
×
31 ⋅ 13
41 ⋅ 43
=
4 × 3
256
=0.0469 = 4.7%
Incorrect
⟮  7  ⟯
3
(¾)4⋅(¼)3=
7!
(7–3)! ⋅ 3!
(¾)4⋅(¼)3=
7⋅6⋅5
3⋅2
×
34 ⋅ 13
44 ⋅ 43
=
35 × 81
16384
=0.1730 = 17.3%
Correct
⟮  7  ⟯
3
(¼)4⋅(¾)3=
7!
(7–3)! ⋅ 3!
(¼)4⋅(¾)3=
7⋅6⋅5
3⋅2
×
14 ⋅ 33
44 ⋅ 43
=
35 × 27
16384
=0.0577 = 5.8%
Incorrect MC

a0ac_ae6b

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 8 offspring, which expression gives the probability of exactly 3 purple and 5 white, in any order?

⟮  3  ⟯
3
(¼)0⋅(¾)3=
3!
(3–3)! ⋅ 3!
(¼)0⋅(¾)3=
1
1
×
10 ⋅ 33
40 ⋅ 43
=
1 × 27
64
=0.4219 = 42.2%
Incorrect
⟮  5  ⟯
3
(¾)2⋅(¼)3=
5!
(5–3)! ⋅ 3!
(¾)2⋅(¼)3=
5⋅4
2
×
32 ⋅ 13
42 ⋅ 43
=
10 × 9
1024
=0.0879 = 8.8%
Incorrect
⟮  8  ⟯
3
(¼)5⋅(¾)3=
8!
(8–3)! ⋅ 3!
(¼)5⋅(¾)3=
8⋅7⋅6
3⋅2
×
15 ⋅ 33
45 ⋅ 43
=
56 × 27
65536
=0.0231 = 2.3%
Correct
⟮  8  ⟯
3
(¾)5⋅(¼)3=
8!
(8–3)! ⋅ 3!
(¾)5⋅(¼)3=
8⋅7⋅6
3⋅2
×
35 ⋅ 13
45 ⋅ 43
=
56 × 243
65536
=0.2076 = 20.8%
Incorrect MC

0dc9_c5ec

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 9 offspring, which expression gives the probability of exactly 4 brown and 5 black, in any order?

⟮  5  ⟯
4
(¾)1⋅(¼)4=
5!
(5–4)! ⋅ 4!
(¾)1⋅(¼)4=
5
1
×
31 ⋅ 14
41 ⋅ 44
=
5 × 3
1024
=0.0146 = 1.5%
Incorrect
⟮  9  ⟯
4
(¾)5⋅(¼)4=
9!
(9–4)! ⋅ 4!
(¾)5⋅(¼)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
35 ⋅ 14
45 ⋅ 44
=
126 × 243
262144
=0.1168 = 11.7%
Correct
⟮  9  ⟯
9
(¼)0⋅(¾)9=
9!
(9–9)! ⋅ 9!
(¼)0⋅(¾)9=
1
1
×
10 ⋅ 39
40 ⋅ 49
=
1 × 19683
262144
=0.0751 = 7.5%
Incorrect
⟮  5  ⟯
4
(¼)1⋅(¾)4=
5!
(5–4)! ⋅ 4!
(¼)1⋅(¾)4=
5
1
×
11 ⋅ 34
41 ⋅ 44
=
5 × 81
1024
=0.3955 = 39.6%
Incorrect MC

4b8f_4557

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 7 offspring, which expression gives the probability of exactly 3 purple and 4 white, in any order?

⟮  3  ⟯
3
(¾)0⋅(¼)3=
3!
(3–3)! ⋅ 3!
(¾)0⋅(¼)3=
1
1
×
30 ⋅ 13
40 ⋅ 43
=
1
64
=0.0156 = 1.6%
Incorrect
⟮  7  ⟯
3
(¼)4⋅(¾)3=
7!
(7–3)! ⋅ 3!
(¼)4⋅(¾)3=
7⋅6⋅5
3⋅2
×
14 ⋅ 33
44 ⋅ 43
=
35 × 27
16384
=0.0577 = 5.8%
Correct
⟮  7  ⟯
4
(¼)3⋅(¾)4=
7!
(7–4)! ⋅ 4!
(¼)3⋅(¾)4=
7⋅6⋅5
3⋅2
×
13 ⋅ 34
43 ⋅ 44
=
35 × 81
16384
=0.1730 = 17.3%
Incorrect
⟮  4  ⟯
4
(¼)0⋅(¾)4=
4!
(4–4)! ⋅ 4!
(¼)0⋅(¾)4=
1
1
×
10 ⋅ 34
40 ⋅ 44
=
1 × 81
256
=0.3164 = 31.6%
Incorrect MC

e0f0_ac20

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 6 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 4 long-tailed, in any order?

⟮  6  ⟯
2
(⅔)4⋅(⅓)2=
6!
(6–2)! ⋅ 2!
(⅔)4⋅(⅓)2=
6⋅5
2
×
24 ⋅ 12
34 ⋅ 32
=
15 × 16
729
=0.3292 = 32.9%
Incorrect
⟮  4  ⟯
4
(⅓)0⋅(⅔)4=
4!
(4–4)! ⋅ 4!
(⅓)0⋅(⅔)4=
1
1
×
10 ⋅ 24
30 ⋅ 34
=
1 × 16
81
=0.1975 = 19.8%
Incorrect
⟮  6  ⟯
2
(⅓)4⋅(⅔)2=
6!
(6–2)! ⋅ 2!
(⅓)4⋅(⅔)2=
6⋅5
2
×
14 ⋅ 22
34 ⋅ 32
=
15 × 4
729
=0.0823 = 8.2%
Correct
⟮  2  ⟯
2
(⅓)0⋅(⅔)2=
2!
(2–2)! ⋅ 2!
(⅓)0⋅(⅔)2=
1
1
×
10 ⋅ 22
30 ⋅ 32
=
1 × 4
9
=0.4444 = 44.4%
Incorrect MC

a0ac_227a

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 8 offspring, which expression gives the probability of exactly 3 purple and 5 white, in any order?

⟮  8  ⟯
3
(¼)5⋅(¾)3=
8!
(8–3)! ⋅ 3!
(¼)5⋅(¾)3=
8⋅7⋅6
3⋅2
×
15 ⋅ 33
45 ⋅ 43
=
56 × 27
65536
=0.0231 = 2.3%
Correct
⟮  5  ⟯
3
(¾)2⋅(¼)3=
5!
(5–3)! ⋅ 3!
(¾)2⋅(¼)3=
5⋅4
2
×
32 ⋅ 13
42 ⋅ 43
=
10 × 9
1024
=0.0879 = 8.8%
Incorrect
⟮  5  ⟯
5
(¼)0⋅(¾)5=
5!
(5–5)! ⋅ 5!
(¼)0⋅(¾)5=
1
1
×
10 ⋅ 35
40 ⋅ 45
=
1 × 243
1024
=0.2373 = 23.7%
Incorrect
⟮  8  ⟯
8
(¼)0⋅(¾)8=
8!
(8–8)! ⋅ 8!
(¼)0⋅(¾)8=
1
1
×
10 ⋅ 38
40 ⋅ 48
=
1 × 6561
65536
=0.1001 = 10.0%
Incorrect MC

4b8f_76f6

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 7 offspring, which expression gives the probability of exactly 3 purple and 4 white, in any order?

⟮  4  ⟯
3
(¼)1⋅(¾)3=
4!
(4–3)! ⋅ 3!
(¼)1⋅(¾)3=
4
1
×
11 ⋅ 33
41 ⋅ 43
=
4 × 27
256
=0.4219 = 42.2%
Incorrect
⟮  7  ⟯
3
(¼)4⋅(¾)3=
7!
(7–3)! ⋅ 3!
(¼)4⋅(¾)3=
7⋅6⋅5
3⋅2
×
14 ⋅ 33
44 ⋅ 43
=
35 × 27
16384
=0.0577 = 5.8%
Correct
⟮  4  ⟯
3
(¾)1⋅(¼)3=
4!
(4–3)! ⋅ 3!
(¾)1⋅(¼)3=
4
1
×
31 ⋅ 13
41 ⋅ 43
=
4 × 3
256
=0.0469 = 4.7%
Incorrect
⟮  7  ⟯
7
(¼)0⋅(¾)7=
7!
(7–7)! ⋅ 7!
(¼)0⋅(¾)7=
1
1
×
10 ⋅ 37
40 ⋅ 47
=
1 × 2187
16384
=0.1335 = 13.3%
Incorrect MC

a0ac_fd0c

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 8 offspring, which expression gives the probability of exactly 3 purple and 5 white, in any order?

⟮  8  ⟯
3
(¼)5⋅(¾)3=
8!
(8–3)! ⋅ 3!
(¼)5⋅(¾)3=
8⋅7⋅6
3⋅2
×
15 ⋅ 33
45 ⋅ 43
=
56 × 27
65536
=0.0231 = 2.3%
Correct
⟮  8  ⟯
5
(¼)3⋅(¾)5=
8!
(8–5)! ⋅ 5!
(¼)3⋅(¾)5=
8⋅7⋅6
3⋅2
×
13 ⋅ 35
43 ⋅ 45
=
56 × 243
65536
=0.2076 = 20.8%
Incorrect
⟮  5  ⟯
5
(¼)0⋅(¾)5=
5!
(5–5)! ⋅ 5!
(¼)0⋅(¾)5=
1
1
×
10 ⋅ 35
40 ⋅ 45
=
1 × 243
1024
=0.2373 = 23.7%
Incorrect
⟮  8  ⟯
8
(¼)0⋅(¾)8=
8!
(8–8)! ⋅ 8!
(¼)0⋅(¾)8=
1
1
×
10 ⋅ 38
40 ⋅ 48
=
1 × 6561
65536
=0.1001 = 10.0%
Incorrect MC

95dc_84b9

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 8 offspring, which expression gives the probability of exactly 3 brown and 5 black, in any order?

⟮  8  ⟯
3
(¾)5⋅(¼)3=
8!
(8–3)! ⋅ 3!
(¾)5⋅(¼)3=
8⋅7⋅6
3⋅2
×
35 ⋅ 13
45 ⋅ 43
=
56 × 243
65536
=0.2076 = 20.8%
Correct
⟮  5  ⟯
3
(¼)2⋅(¾)3=
5!
(5–3)! ⋅ 3!
(¼)2⋅(¾)3=
5⋅4
2
×
12 ⋅ 33
42 ⋅ 43
=
10 × 27
1024
=0.2637 = 26.4%
Incorrect
⟮  8  ⟯
8
(¼)0⋅(¾)8=
8!
(8–8)! ⋅ 8!
(¼)0⋅(¾)8=
1
1
×
10 ⋅ 38
40 ⋅ 48
=
1 × 6561
65536
=0.1001 = 10.0%
Incorrect
⟮  8  ⟯
3
(¼)5⋅(¾)3=
8!
(8–3)! ⋅ 3!
(¼)5⋅(¾)3=
8⋅7⋅6
3⋅2
×
15 ⋅ 33
45 ⋅ 43
=
56 × 27
65536
=0.0231 = 2.3%
Incorrect MC

e13d_5c98

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 7 surviving offspring, which expression gives the probability of exactly 3 short-tailed and 4 long-tailed, in any order?

⟮  3  ⟯
3
(⅔)0⋅(⅓)3=
3!
(3–3)! ⋅ 3!
(⅔)0⋅(⅓)3=
1
1
×
20 ⋅ 13
30 ⋅ 33
=
1
27
=0.0370 = 3.7%
Incorrect
⟮  7  ⟯
4
(⅓)3⋅(⅔)4=
7!
(7–4)! ⋅ 4!
(⅓)3⋅(⅔)4=
7⋅6⋅5
3⋅2
×
13 ⋅ 24
33 ⋅ 34
=
35 × 16
2187
=0.2561 = 25.6%
Incorrect
⟮  4  ⟯
3
(⅔)1⋅(⅓)3=
4!
(4–3)! ⋅ 3!
(⅔)1⋅(⅓)3=
4
1
×
21 ⋅ 13
31 ⋅ 33
=
4 × 2
81
=0.0988 = 9.9%
Incorrect
⟮  7  ⟯
3
(⅓)4⋅(⅔)3=
7!
(7–3)! ⋅ 3!
(⅓)4⋅(⅔)3=
7⋅6⋅5
3⋅2
×
14 ⋅ 23
34 ⋅ 33
=
35 × 8
2187
=0.1280 = 12.8%
Correct MC

97f7_f012

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 6 offspring, which expression gives the probability of exactly 2 brown and 4 black, in any order?

(1/4)2 × (3/4)4=0.0198 = 2.0%
Incorrect
⟮  2  ⟯
2
(¼)0⋅(¾)2=
2!
(2–2)! ⋅ 2!
(¼)0⋅(¾)2=
1
1
×
10 ⋅ 32
40 ⋅ 42
=
1 × 9
16
=0.5625 = 56.2%
Incorrect
⟮  6  ⟯
2
(¾)4⋅(¼)2=
6!
(6–2)! ⋅ 2!
(¾)4⋅(¼)2=
6⋅5
2
×
34 ⋅ 12
44 ⋅ 42
=
15 × 81
4096
=0.2966 = 29.7%
Correct
⟮  4  ⟯
2
(¼)2⋅(¾)2=
4!
(4–2)! ⋅ 2!
(¼)2⋅(¾)2=
4⋅3
2
×
12 ⋅ 32
42 ⋅ 42
=
6 × 9
256
=0.2109 = 21.1%
Incorrect MC

a1a4_ca2b

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 5 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 3 long-tailed, in any order?

⟮  5  ⟯
2
(⅓)3⋅(⅔)2=
5!
(5–2)! ⋅ 2!
(⅓)3⋅(⅔)2=
5⋅4
2
×
13 ⋅ 22
33 ⋅ 32
=
10 × 4
243
=0.1646 = 16.5%
Correct
⟮  3  ⟯
2
(⅓)1⋅(⅔)2=
3!
(3–2)! ⋅ 2!
(⅓)1⋅(⅔)2=
3
1
×
11 ⋅ 22
31 ⋅ 32
=
3 × 4
27
=0.4444 = 44.4%
Incorrect
⟮  5  ⟯
3
(⅓)2⋅(⅔)3=
5!
(5–3)! ⋅ 3!
(⅓)2⋅(⅔)3=
5⋅4
2
×
12 ⋅ 23
32 ⋅ 33
=
10 × 8
243
=0.3292 = 32.9%
Incorrect
⟮  3  ⟯
3
(⅓)0⋅(⅔)3=
3!
(3–3)! ⋅ 3!
(⅓)0⋅(⅔)3=
1
1
×
10 ⋅ 23
30 ⋅ 33
=
1 × 8
27
=0.2963 = 29.6%
Incorrect MC

97f7_8d35

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 6 offspring, which expression gives the probability of exactly 2 brown and 4 black, in any order?

(1/4)2 × (3/4)4=0.0198 = 2.0%
Incorrect
⟮  6  ⟯
4
(¾)2⋅(¼)4=
6!
(6–4)! ⋅ 4!
(¾)2⋅(¼)4=
6⋅5
2
×
32 ⋅ 14
42 ⋅ 44
=
15 × 9
4096
=0.0330 = 3.3%
Incorrect
⟮  6  ⟯
2
(¾)4⋅(¼)2=
6!
(6–2)! ⋅ 2!
(¾)4⋅(¼)2=
6⋅5
2
×
34 ⋅ 12
44 ⋅ 42
=
15 × 81
4096
=0.2966 = 29.7%
Correct
⟮  4  ⟯
2
(¾)2⋅(¼)2=
4!
(4–2)! ⋅ 2!
(¾)2⋅(¼)2=
4⋅3
2
×
32 ⋅ 12
42 ⋅ 42
=
6 × 9
256
=0.2109 = 21.1%
Incorrect MC

322c_d8b9

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 7 offspring, which expression gives the probability of exactly 3 brown and 4 black, in any order?

⟮  4  ⟯
3
(¼)1⋅(¾)3=
4!
(4–3)! ⋅ 3!
(¼)1⋅(¾)3=
4
1
×
11 ⋅ 33
41 ⋅ 43
=
4 × 27
256
=0.4219 = 42.2%
Incorrect
⟮  7  ⟯
3
(¼)4⋅(¾)3=
7!
(7–3)! ⋅ 3!
(¼)4⋅(¾)3=
7⋅6⋅5
3⋅2
×
14 ⋅ 33
44 ⋅ 43
=
35 × 27
16384
=0.0577 = 5.8%
Incorrect
⟮  7  ⟯
3
(¾)4⋅(¼)3=
7!
(7–3)! ⋅ 3!
(¾)4⋅(¼)3=
7⋅6⋅5
3⋅2
×
34 ⋅ 13
44 ⋅ 43
=
35 × 81
16384
=0.1730 = 17.3%
Correct
⟮  7  ⟯
7
(¼)0⋅(¾)7=
7!
(7–7)! ⋅ 7!
(¼)0⋅(¾)7=
1
1
×
10 ⋅ 37
40 ⋅ 47
=
1 × 2187
16384
=0.1335 = 13.3%
Incorrect MC

e13d_448a

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 7 surviving offspring, which expression gives the probability of exactly 3 short-tailed and 4 long-tailed, in any order?

⟮  7  ⟯
3
(⅔)4⋅(⅓)3=
7!
(7–3)! ⋅ 3!
(⅔)4⋅(⅓)3=
7⋅6⋅5
3⋅2
×
24 ⋅ 13
34 ⋅ 33
=
35 × 16
2187
=0.2561 = 25.6%
Incorrect
⟮  3  ⟯
3
(⅔)0⋅(⅓)3=
3!
(3–3)! ⋅ 3!
(⅔)0⋅(⅓)3=
1
1
×
20 ⋅ 13
30 ⋅ 33
=
1
27
=0.0370 = 3.7%
Incorrect
⟮  4  ⟯
4
(⅓)0⋅(⅔)4=
4!
(4–4)! ⋅ 4!
(⅓)0⋅(⅔)4=
1
1
×
10 ⋅ 24
30 ⋅ 34
=
1 × 16
81
=0.1975 = 19.8%
Incorrect
⟮  7  ⟯
3
(⅓)4⋅(⅔)3=
7!
(7–3)! ⋅ 3!
(⅓)4⋅(⅔)3=
7⋅6⋅5
3⋅2
×
14 ⋅ 23
34 ⋅ 33
=
35 × 8
2187
=0.1280 = 12.8%
Correct MC

2923_b7ca

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 8 surviving offspring, which expression gives the probability of exactly 3 short-tailed and 5 long-tailed, in any order?

⟮  8  ⟯
8
(⅓)0⋅(⅔)8=
8!
(8–8)! ⋅ 8!
(⅓)0⋅(⅔)8=
1
1
×
10 ⋅ 28
30 ⋅ 38
=
1 × 256
6561
=0.0390 = 3.9%
Incorrect
⟮  5  ⟯
3
(⅓)2⋅(⅔)3=
5!
(5–3)! ⋅ 3!
(⅓)2⋅(⅔)3=
5⋅4
2
×
12 ⋅ 23
32 ⋅ 33
=
10 × 8
243
=0.3292 = 32.9%
Incorrect
⟮  8  ⟯
3
(⅓)5⋅(⅔)3=
8!
(8–3)! ⋅ 3!
(⅓)5⋅(⅔)3=
8⋅7⋅6
3⋅2
×
15 ⋅ 23
35 ⋅ 33
=
56 × 8
6561
=0.0683 = 6.8%
Correct
⟮  5  ⟯
3
(⅔)2⋅(⅓)3=
5!
(5–3)! ⋅ 3!
(⅔)2⋅(⅓)3=
5⋅4
2
×
22 ⋅ 13
32 ⋅ 33
=
10 × 4
243
=0.1646 = 16.5%
Incorrect MC

0dc9_aba5

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 9 offspring, which expression gives the probability of exactly 4 brown and 5 black, in any order?

⟮  5  ⟯
5
(¼)0⋅(¾)5=
5!
(5–5)! ⋅ 5!
(¼)0⋅(¾)5=
1
1
×
10 ⋅ 35
40 ⋅ 45
=
1 × 243
1024
=0.2373 = 23.7%
Incorrect
⟮  9  ⟯
4
(¾)5⋅(¼)4=
9!
(9–4)! ⋅ 4!
(¾)5⋅(¼)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
35 ⋅ 14
45 ⋅ 44
=
126 × 243
262144
=0.1168 = 11.7%
Correct
⟮  5  ⟯
4
(¾)1⋅(¼)4=
5!
(5–4)! ⋅ 4!
(¾)1⋅(¼)4=
5
1
×
31 ⋅ 14
41 ⋅ 44
=
5 × 3
1024
=0.0146 = 1.5%
Incorrect
⟮  9  ⟯
4
×(1/4)4=0.4922 = 49.2%
Incorrect MC

9ff2_0e1c

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 5 offspring, which expression gives the probability of exactly 2 brown and 3 black, in any order?

⟮  3  ⟯
2
(¾)1⋅(¼)2=
3!
(3–2)! ⋅ 2!
(¾)1⋅(¼)2=
3
1
×
31 ⋅ 12
41 ⋅ 42
=
3 × 3
64
=0.1406 = 14.1%
Incorrect
⟮  5  ⟯
3
(¾)2⋅(¼)3=
5!
(5–3)! ⋅ 3!
(¾)2⋅(¼)3=
5⋅4
2
×
32 ⋅ 13
42 ⋅ 43
=
10 × 9
1024
=0.0879 = 8.8%
Incorrect
⟮  5  ⟯
2
(¾)3⋅(¼)2=
5!
(5–2)! ⋅ 2!
(¾)3⋅(¼)2=
5⋅4
2
×
33 ⋅ 12
43 ⋅ 42
=
10 × 27
1024
=0.2637 = 26.4%
Correct
⟮  3  ⟯
3
(¼)0⋅(¾)3=
3!
(3–3)! ⋅ 3!
(¼)0⋅(¾)3=
1
1
×
10 ⋅ 33
40 ⋅ 43
=
1 × 27
64
=0.4219 = 42.2%
Incorrect MC

832f_7706

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 9 surviving offspring, which expression gives the probability of exactly 4 short-tailed and 5 long-tailed, in any order?

⟮  9  ⟯
9
(⅓)0⋅(⅔)9=
9!
(9–9)! ⋅ 9!
(⅓)0⋅(⅔)9=
1
1
×
10 ⋅ 29
30 ⋅ 39
=
1 × 512
19683
=0.0260 = 2.6%
Incorrect
⟮  4  ⟯
4
(⅔)0⋅(⅓)4=
4!
(4–4)! ⋅ 4!
(⅔)0⋅(⅓)4=
1
1
×
20 ⋅ 14
30 ⋅ 34
=
1
81
=0.0123 = 1.2%
Incorrect
⟮  4  ⟯
4
(⅓)0⋅(⅔)4=
4!
(4–4)! ⋅ 4!
(⅓)0⋅(⅔)4=
1
1
×
10 ⋅ 24
30 ⋅ 34
=
1 × 16
81
=0.1975 = 19.8%
Incorrect
⟮  9  ⟯
4
(⅓)5⋅(⅔)4=
9!
(9–4)! ⋅ 4!
(⅓)5⋅(⅔)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 24
35 ⋅ 34
=
126 × 16
19683
=0.1024 = 10.2%
Correct MC

9ff2_7de7

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 5 offspring, which expression gives the probability of exactly 2 brown and 3 black, in any order?

⟮  5  ⟯
2
(¾)3⋅(¼)2=
5!
(5–2)! ⋅ 2!
(¾)3⋅(¼)2=
5⋅4
2
×
33 ⋅ 12
43 ⋅ 42
=
10 × 27
1024
=0.2637 = 26.4%
Correct
⟮  3  ⟯
3
(¾)0⋅(¼)3=
3!
(3–3)! ⋅ 3!
(¾)0⋅(¼)3=
1
1
×
30 ⋅ 13
40 ⋅ 43
=
1
64
=0.0156 = 1.6%
Incorrect
⟮  2  ⟯
2
(¾)0⋅(¼)2=
2!
(2–2)! ⋅ 2!
(¾)0⋅(¼)2=
1
1
×
30 ⋅ 12
40 ⋅ 42
=
1
16
=0.0625 = 6.2%
Incorrect
⟮  5  ⟯
5
(¼)0⋅(¾)5=
5!
(5–5)! ⋅ 5!
(¼)0⋅(¾)5=
1
1
×
10 ⋅ 35
40 ⋅ 45
=
1 × 243
1024
=0.2373 = 23.7%
Incorrect MC

0dc9_c605

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 9 offspring, which expression gives the probability of exactly 4 brown and 5 black, in any order?

⟮  9  ⟯
9
(¼)0⋅(¾)9=
9!
(9–9)! ⋅ 9!
(¼)0⋅(¾)9=
1
1
×
10 ⋅ 39
40 ⋅ 49
=
1 × 19683
262144
=0.0751 = 7.5%
Incorrect
⟮  5  ⟯
4
(¼)1⋅(¾)4=
5!
(5–4)! ⋅ 4!
(¼)1⋅(¾)4=
5
1
×
11 ⋅ 34
41 ⋅ 44
=
5 × 81
1024
=0.3955 = 39.6%
Incorrect
⟮  9  ⟯
4
(¼)5⋅(¾)4=
9!
(9–4)! ⋅ 4!
(¼)5⋅(¾)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 34
45 ⋅ 44
=
126 × 81
262144
=0.0389 = 3.9%
Incorrect
⟮  9  ⟯
4
(¾)5⋅(¼)4=
9!
(9–4)! ⋅ 4!
(¾)5⋅(¼)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
35 ⋅ 14
45 ⋅ 44
=
126 × 243
262144
=0.1168 = 11.7%
Correct MC

0dc9_8e7e

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 9 offspring, which expression gives the probability of exactly 4 brown and 5 black, in any order?

⟮  9  ⟯
4
(¾)5⋅(¼)4=
9!
(9–4)! ⋅ 4!
(¾)5⋅(¼)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
35 ⋅ 14
45 ⋅ 44
=
126 × 243
262144
=0.1168 = 11.7%
Correct
⟮  9  ⟯
9
(¼)0⋅(¾)9=
9!
(9–9)! ⋅ 9!
(¼)0⋅(¾)9=
1
1
×
10 ⋅ 39
40 ⋅ 49
=
1 × 19683
262144
=0.0751 = 7.5%
Incorrect
⟮  5  ⟯
4
(¾)1⋅(¼)4=
5!
(5–4)! ⋅ 4!
(¾)1⋅(¼)4=
5
1
×
31 ⋅ 14
41 ⋅ 44
=
5 × 3
1024
=0.0146 = 1.5%
Incorrect
⟮  9  ⟯
4
×(1/4)4=0.4922 = 49.2%
Incorrect MC

9ff2_ba49

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 5 offspring, which expression gives the probability of exactly 2 brown and 3 black, in any order?

⟮  5  ⟯
2
(¼)3⋅(¾)2=
5!
(5–2)! ⋅ 2!
(¼)3⋅(¾)2=
5⋅4
2
×
13 ⋅ 32
43 ⋅ 42
=
10 × 9
1024
=0.0879 = 8.8%
Incorrect
⟮  3  ⟯
3
(¾)0⋅(¼)3=
3!
(3–3)! ⋅ 3!
(¾)0⋅(¼)3=
1
1
×
30 ⋅ 13
40 ⋅ 43
=
1
64
=0.0156 = 1.6%
Incorrect
(1/4)2 × (3/4)3=0.0264 = 2.6%
Incorrect
⟮  5  ⟯
2
(¾)3⋅(¼)2=
5!
(5–2)! ⋅ 2!
(¾)3⋅(¼)2=
5⋅4
2
×
33 ⋅ 12
43 ⋅ 42
=
10 × 27
1024
=0.2637 = 26.4%
Correct MC

a0ac_deb3

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 8 offspring, which expression gives the probability of exactly 3 purple and 5 white, in any order?

⟮  8  ⟯
3
(¼)5⋅(¾)3=
8!
(8–3)! ⋅ 3!
(¼)5⋅(¾)3=
8⋅7⋅6
3⋅2
×
15 ⋅ 33
45 ⋅ 43
=
56 × 27
65536
=0.0231 = 2.3%
Correct
⟮  8  ⟯
8
(¼)0⋅(¾)8=
8!
(8–8)! ⋅ 8!
(¼)0⋅(¾)8=
1
1
×
10 ⋅ 38
40 ⋅ 48
=
1 × 6561
65536
=0.1001 = 10.0%
Incorrect
⟮  3  ⟯
3
(¼)0⋅(¾)3=
3!
(3–3)! ⋅ 3!
(¼)0⋅(¾)3=
1
1
×
10 ⋅ 33
40 ⋅ 43
=
1 × 27
64
=0.4219 = 42.2%
Incorrect
⟮  8  ⟯
5
(¼)3⋅(¾)5=
8!
(8–5)! ⋅ 5!
(¼)3⋅(¾)5=
8⋅7⋅6
3⋅2
×
13 ⋅ 35
43 ⋅ 45
=
56 × 243
65536
=0.2076 = 20.8%
Incorrect MC

a1a4_f42a

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 5 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 3 long-tailed, in any order?

⟮  3  ⟯
3
(⅔)0⋅(⅓)3=
3!
(3–3)! ⋅ 3!
(⅔)0⋅(⅓)3=
1
1
×
20 ⋅ 13
30 ⋅ 33
=
1
27
=0.0370 = 3.7%
Incorrect
⟮  5  ⟯
2
(⅔)3⋅(⅓)2=
5!
(5–2)! ⋅ 2!
(⅔)3⋅(⅓)2=
5⋅4
2
×
23 ⋅ 12
33 ⋅ 32
=
10 × 8
243
=0.3292 = 32.9%
Incorrect
⟮  3  ⟯
2
(⅓)1⋅(⅔)2=
3!
(3–2)! ⋅ 2!
(⅓)1⋅(⅔)2=
3
1
×
11 ⋅ 22
31 ⋅ 32
=
3 × 4
27
=0.4444 = 44.4%
Incorrect
⟮  5  ⟯
2
(⅓)3⋅(⅔)2=
5!
(5–2)! ⋅ 2!
(⅓)3⋅(⅔)2=
5⋅4
2
×
13 ⋅ 22
33 ⋅ 32
=
10 × 4
243
=0.1646 = 16.5%
Correct MC

e0f0_d856

Offspring phenotypeProbability for one offspring
short-tailed2/3
long-tailed1/3

You cross two (2) short-tailed mice (Tt × Tt). TT offspring do not survive. Among surviving offspring, Tt mice have short tails and tt mice have long tails.

Offspring outcomes are independent.

For 6 surviving offspring, which expression gives the probability of exactly 2 short-tailed and 4 long-tailed, in any order?

⟮  6  ⟯
2
(⅓)4⋅(⅔)2=
6!
(6–2)! ⋅ 2!
(⅓)4⋅(⅔)2=
6⋅5
2
×
14 ⋅ 22
34 ⋅ 32
=
15 × 4
729
=0.0823 = 8.2%
Correct
⟮  4  ⟯
2
(⅓)2⋅(⅔)2=
4!
(4–2)! ⋅ 2!
(⅓)2⋅(⅔)2=
4⋅3
2
×
12 ⋅ 22
32 ⋅ 32
=
6 × 4
81
=0.2963 = 29.6%
Incorrect
⟮  4  ⟯
4
(⅔)0⋅(⅓)4=
4!
(4–4)! ⋅ 4!
(⅔)0⋅(⅓)4=
1
1
×
20 ⋅ 14
30 ⋅ 34
=
1
81
=0.0123 = 1.2%
Incorrect
⟮  6  ⟯
2
(⅔)4⋅(⅓)2=
6!
(6–2)! ⋅ 2!
(⅔)4⋅(⅓)2=
6⋅5
2
×
24 ⋅ 12
34 ⋅ 32
=
15 × 16
729
=0.3292 = 32.9%
Incorrect MC

cb40_1445

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 5 offspring, which expression gives the probability of exactly 2 purple and 3 white, in any order?

⟮  5  ⟯
3
(¼)2⋅(¾)3=
5!
(5–3)! ⋅ 3!
(¼)2⋅(¾)3=
5⋅4
2
×
12 ⋅ 33
42 ⋅ 43
=
10 × 27
1024
=0.2637 = 26.4%
Incorrect
(3/4)2 × (1/4)3=0.0088 = 0.9%
Incorrect
⟮  5  ⟯
2
(¼)3⋅(¾)2=
5!
(5–2)! ⋅ 2!
(¼)3⋅(¾)2=
5⋅4
2
×
13 ⋅ 32
43 ⋅ 42
=
10 × 9
1024
=0.0879 = 8.8%
Correct
⟮  3  ⟯
2
(¼)1⋅(¾)2=
3!
(3–2)! ⋅ 2!
(¼)1⋅(¾)2=
3
1
×
11 ⋅ 32
41 ⋅ 42
=
3 × 9
64
=0.4219 = 42.2%
Incorrect MC

b71d_caee

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 9 offspring, which expression gives the probability of exactly 4 purple and 5 white, in any order?

⟮  4  ⟯
4
(¼)0⋅(¾)4=
4!
(4–4)! ⋅ 4!
(¼)0⋅(¾)4=
1
1
×
10 ⋅ 34
40 ⋅ 44
=
1 × 81
256
=0.3164 = 31.6%
Incorrect
⟮  9  ⟯
4
(¾)5⋅(¼)4=
9!
(9–4)! ⋅ 4!
(¾)5⋅(¼)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
35 ⋅ 14
45 ⋅ 44
=
126 × 243
262144
=0.1168 = 11.7%
Incorrect
⟮  5  ⟯
4
(¼)1⋅(¾)4=
5!
(5–4)! ⋅ 4!
(¼)1⋅(¾)4=
5
1
×
11 ⋅ 34
41 ⋅ 44
=
5 × 81
1024
=0.3955 = 39.6%
Incorrect
⟮  9  ⟯
4
(¼)5⋅(¾)4=
9!
(9–4)! ⋅ 4!
(¼)5⋅(¾)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 34
45 ⋅ 44
=
126 × 81
262144
=0.0389 = 3.9%
Correct MC

97f7_3804

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 6 offspring, which expression gives the probability of exactly 2 brown and 4 black, in any order?

⟮  4  ⟯
2
(¾)2⋅(¼)2=
4!
(4–2)! ⋅ 2!
(¾)2⋅(¼)2=
4⋅3
2
×
32 ⋅ 12
42 ⋅ 42
=
6 × 9
256
=0.2109 = 21.1%
Incorrect
⟮  6  ⟯
2
(¾)4⋅(¼)2=
6!
(6–2)! ⋅ 2!
(¾)4⋅(¼)2=
6⋅5
2
×
34 ⋅ 12
44 ⋅ 42
=
15 × 81
4096
=0.2966 = 29.7%
Correct
⟮  2  ⟯
2
(¾)0⋅(¼)2=
2!
(2–2)! ⋅ 2!
(¾)0⋅(¼)2=
1
1
×
30 ⋅ 12
40 ⋅ 42
=
1
16
=0.0625 = 6.2%
Incorrect
⟮  2  ⟯
2
(¼)0⋅(¾)2=
2!
(2–2)! ⋅ 2!
(¼)0⋅(¾)2=
1
1
×
10 ⋅ 32
40 ⋅ 42
=
1 × 9
16
=0.5625 = 56.2%
Incorrect MC

b71d_121c

Offspring phenotypeProbability for one offspring
purple3/4
white1/4

You cross two (2) purple-flowered pea plants (Pp × Pp).

Offspring outcomes are independent.

For 9 offspring, which expression gives the probability of exactly 4 purple and 5 white, in any order?

⟮  9  ⟯
9
(¼)0⋅(¾)9=
9!
(9–9)! ⋅ 9!
(¼)0⋅(¾)9=
1
1
×
10 ⋅ 39
40 ⋅ 49
=
1 × 19683
262144
=0.0751 = 7.5%
Incorrect
⟮  5  ⟯
5
(¼)0⋅(¾)5=
5!
(5–5)! ⋅ 5!
(¼)0⋅(¾)5=
1
1
×
10 ⋅ 35
40 ⋅ 45
=
1 × 243
1024
=0.2373 = 23.7%
Incorrect
⟮  9  ⟯
4
(¼)5⋅(¾)4=
9!
(9–4)! ⋅ 4!
(¼)5⋅(¾)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
15 ⋅ 34
45 ⋅ 44
=
126 × 81
262144
=0.0389 = 3.9%
Correct
⟮  9  ⟯
4
(¾)5⋅(¼)4=
9!
(9–4)! ⋅ 4!
(¾)5⋅(¼)4=
9⋅8⋅7⋅6
4⋅3⋅2
×
35 ⋅ 14
45 ⋅ 44
=
126 × 243
262144
=0.1168 = 11.7%
Incorrect MC

322c_72da

Offspring phenotypeProbability for one offspring
brown1/4
black3/4

You cross two (2) heterozygous mice (Bb × Bb). Black fur is dominant to brown fur.

Offspring outcomes are independent.

For 7 offspring, which expression gives the probability of exactly 3 brown and 4 black, in any order?

⟮  7  ⟯
4
(¾)3⋅(¼)4=
7!
(7–4)! ⋅ 4!
(¾)3⋅(¼)4=
7⋅6⋅5
3⋅2
×
33 ⋅ 14
43 ⋅ 44
=
35 × 27
16384
=0.0577 = 5.8%
Incorrect
⟮  3  ⟯
3
(¼)0⋅(¾)3=
3!
(3–3)! ⋅ 3!
(¼)0⋅(¾)3=
1
1
×
10 ⋅ 33
40 ⋅ 43
=
1 × 27
64
=0.4219 = 42.2%
Incorrect
⟮  3  ⟯
3
(¾)0⋅(¼)3=
3!
(3–3)! ⋅ 3!
(¾)0⋅(¼)3=
1
1
×
30 ⋅ 13
40 ⋅ 43
=
1
64
=0.0156 = 1.6%
Incorrect
⟮  7  ⟯
3
(¾)4⋅(¼)3=
7!
(7–3)! ⋅ 3!
(¾)4⋅(¼)3=
7⋅6⋅5
3⋅2
×
34 ⋅ 13
44 ⋅ 43
=
35 × 81
16384
=0.1730 = 17.3%
Correct