Question

Enter 1 if it is true else enter 0.

A bag contains $3$ red balls, $5$ black balls and $4$ white balls. A ball is drawn at random from the bag. The probability that the ball drawn is white is $\frac{1}{3}$

Answer 1

Number of red balls $=3$

Number of black balls $=5$

Number of white balls $=4$

Total number of balls $=3+5+4=12$

$\therefore$ the total number of cases $=12$

SInce there are $4$ white balls, the number of favourable outcomes is $4$

Hence, P(a white ball) $=\frac{\text{Number of favourable cases}}{\text{Total number of cases}}=\frac{4}{12}=\frac{1}{3}$