Question

A box contains 25 cards numbered from 1 to 25. A card is drawn at random from the bag. Find the probability that the number on the drawn card is a prime number.

Answer 1

Total number of outcomes = 25

Let E₂ be the event of getting a prime number.

Out of the given numbers, prime numbers are 2, 3, 5, 7, 11, 13, 17, 19 and 23.

Number of favourable outcomes = 9

∴ P(getting a prime number) = P(E₂) = `("Number of outcomes favourable to" E_2)/"Number of all possible outcomes"`

`= 9/25`

Thus, the probability that the number on the drawn card is a prime number is `9/25`.