WAEC - Mathematics (2002 - No. 25)

A number is selected at random from the set Y = {18, 19, 20, . . . 28, 29}. Find the probability that the number is prime.

\(\frac{1}{4}\)

\(\frac{3}{11}\)

\(\frac{1}{2}\)

\(\frac{3}{4}\)

Y = {18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29}

Number of prime numbers = 3

Prob(picking a prime number) = \(\frac{3}{12}\)

= \(\frac{1}{4}\)