Question

determine twofifth of a collection of 40 balls​

Answer 1

Answer:

Answer

Let no. of red balls = x, no. of blue balls =y and no.of black balls = z.

Probability of drawing a red ball = P (red ball) =2011=40x

⇒ x=22

Probability of drawing a blue ball = P (Blue ball) = 51=40y

⇒ y=8

∴ No of black balls = 40- 22 -8 =10