Find the probability of the teacher choosing 2 sophomores, then 2 freshman.

Question

A teacher chooses 4 different students to answer questions. There are 21 sophomores and 8 freshman. Find the probability of the teacher choosing 2 sophomores, then 2 freshman.

Answer 1

Choosing 2 sophomores out of 21, so 21C2 combinations

Choosing 2 freshmen out of 8, so 8C2 combinations

Total combinations of sophomores and freshmen is 21C2 * 8C2

Choosing 4 students out of 29 total, so 29C4 combinations of students

Probability = total combinations of sophomores and freshman/ total combinations of students