Question

Tickets numbered 2, 3, 4, 5, ..., 100, 101 are placed in a box and mixed thoroughly. One ticket is drawn at random from the box. Find the probability that the number on the ticket is a prime number less than 40.

Answer 1

All possible outcomes are  2, 3, 4, 5................101.

Number of all possible outcomes = 100

Out of these, prime numbers less than 40 = 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37

Let E₄ be the event of getting a prime number less than 40.

Then,​ number of favourable outcomes =​ 12

∴ P (getting a prime number less than 40) = `12/100 = 3/25`