Numerical answer
A committee of 4 people is chosen at random from a group of 6 men and 5 women. If the probability that all 4 selected are men is a/b in its lowest terms, find the value of a+b.
Show answer and solution
Answer: 23
Total ways to choose 4 from 11 people = C(11,4) = 330. Favourable ways (all men) = C(6,4) = 15. So probability = 15/330 = 1/22 (in lowest terms, gcd(1,22)=1). Here a=1, b=22, so a+b = 23.
Saved on this device. Sign in or create a free account to keep it on every device.