Question

A bag contains 12 white and black balls out of which $x$ are black. If one ball is drawn at random, what is the probability it will be a white ball?

• A. $\frac{(12+x)}{12}$
• B. $\frac{(12-x)}{12}$
• C. $\frac{(12-x)}{x}$
• D. $\frac{\left(12x\right)}{12}$

Answer 1

The correct option is B $\frac{(12-x)}{12}$

Probability = $\frac{No.offavourableoutcomes}{Totalno.ofoutcomes}$

Total number of balls = 12

Total number of black balls $=x$

P (getting a black ball) $=\frac{x}{12}$

So, probability of getting a white ball $=\frac{(12-x)}{12}$