Question

The ages of the people on the bus are 24, 38, 47, 29, 51, 44, 40, 31, 36, and 43. If a bus passenger is selected at random, what is the probability that he or she is younger than 30?

Answer 1

We want to know the probability of a passenger to be younger than 30.

There are 10 persons on the bus and out of those, just 2 are younger than 30.

Denote by E the event: "obtaining a person younger than 30 when its selected at random from the bus". Then,

$P(E)=\frac{\text{number of persons younger than 30}}{\text{total persons on the bus}}=\frac{2}{10}=\frac{1}{5}=0.2$

This means that the probability of a passenger to be younger than 30 is 0.2.