Question

A bag contains 24 red and white balls. If the probability of drawing a red ball is twice that of drawing a white, how many white balls are there?

Answer 1

Assume, No. of white balls = x, No. of red balls = 24 - x

The probability of drawing red ball is twice that of drawing a white ball.

From question,

$\frac{24-x}{24}$ = 2 × $\frac{x}{24}$

24 - x = 2x

3x = 24

x = 8

Hence, No. of white balls = 8