Skip to main content
OlympiadHQ

Browse · MATH

Print

jmc

counting and probability junior

Problem

Our club has 20 members, 10 boys and 10 girls. In how many ways can we choose a president and a vice-president if they must be of different gender?
Solution
The president can be any one of the 20 members, and the vice-president can be any one of the 10 members of the opposite sex. The answer is .
Final answer
200