Question

Cards numbered from 11 to 60 are kept in a box. If a card is drawn at random from the box, find the probability that the number on the drawn card isa prime number less than 20   

Answer 1

The cards are numbered from 11 to 60.
∴ Total number of outcomes = 60 − 10 = 50

 Prime numbers less than 20 from 11 to 60 are 11, 13, 17 and 19.
So, the favourable number of outcomes are 4.
∴ P(number on the drawn card is a prime number less than 20) =\[\frac{\text{ Favourable number of outcomes }}{\text{ Total number of outcomes }} = \frac{4}{50} = \frac{2}{25}\]