Question

Find the probability that a number selected at random from the numbers 3, 4, 5, ...., 25 is prime.

Answer 1

All possible outcomes are 3, 4, 5, ...., 25.

Number of all possible outcomes = 23.

Out of these, the prime numbers are 3, 5, 7, 11, 13, 17, 19, 23.

Number of favourable outcomes = 8.

P(getting a prime number) = $\frac{8}{23}$