Question

A number is selected at random from 10 to 25. Find the probability that the number
prime number.​

Answer 1

Let S be the sample space, therefore:

S = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25}

n (S) = 16

Let A be the event of getting a prime number, therefore:

A = {11, 13, 17, 19, 23}

n (A) = 5

$P(A) = \frac{n (A)}{n (S)} \\ \: \: \: \: \: \: \: \: \: \: \: \: = \frac{5}{16}$