Question

A contest of 10 girls has 3 winners. In how many ways can you choose 3 winners if;

A. You select a first, second, and third place?

B. You select a group of 3 winners?

Answer 1

A)

First winner is selected from 10 ways.

Second winner is selected from 9 ways.

Third winner is selected from 8 ways.

Total number ways to select first second and third winner = 10 * 9 * 8 = 720

B)

Group of 3 winners can be selected from 10 students by 10C3 ways.

10C3 = 10! / [ (10 - 3)! * 3! ]

= 120