A bag contains 5 red balls and some blue balls If the probability of drawing a blue ball is double t...

Question

A bag contains 5 red balls and some blue balls If the probability of drawing a blue ball is double that of a red ball determine the number of blue balls in the bag

Accepted Answer

It is given that the total number of red balls = 5

Let the total number of blue balls = x

So, the total no. of balls = x+5

P(E) = (Number of favourable outcomes/ Total number of outcomes)

∴ P (drawing a blue ball) = [x/(x+5)] ——–(i)

Similarly,

P (drawing a red ball) = [5/(x+5)] ——–(i)

From equation (i) and (ii)

x = 10

So, the total number of blue balls = 10

NCERT Solutions Class 10 Mathematics Solutions for Probability - Exercise 15.1 in Chapter 15 - Probability