There are 10 students in a class: 3 boys and 7 girls. If the teacher picks a group of 3 at random, what is the probability that

Question

3 years ago

6

everyone in the group is a girl?

2 answers:

Sladkaya [172] · Answer 1 · 2022-01-29T20:47:05+03:00

8 0

2/3 is the probability

ValentinkaMS [17] · Answer 2 · 2022-01-29T21:48:04+03:00

8 0

Probability the first pick is a girl: 7/10

Probability the second pick is a girl: 6/9

Probability the third pick is a girl: 5/8

Probability of picking 3 girls:

7/10 * 6/9 * 5/8 =

= (7 * 6 * 5)/(10 * 9 * 8)

= (7 * 1 * 1)/(2 * 3 * 4)

=7/24

Approximately 0.29 = 29%