A group has 15 boys and 6 girls. If 3 girls are to be selected without replacement, in how many ways can they be selected?
- 22
- 21
- 20
- None of these
Explanation
Formula: nCr = n! / r!(n-r)!
Here n = 6 girls, r = 3 girls to select
6C3 = 6! / 3!(6-3)!
= 6! / 3!3!
= (6 x 5 x 4) / (3 x 2 x 1)
= 120 / 6
= 20
Last verified on 11-07-2026