Question

A bag contains 5 white balls, 7 red balls, 4 black balls and 2 blue balls. One ball is drawn at random from the bag. What is the probability that the ball drawn is white or blue.

Answer 1

Given: A bag contains 5 white balls, 7 red balls, 4 black balls and 2 blue balls; one ball is drawn at random.

Step-wise calculation:

1. Total number of balls

= 5 + 7 + 4 + 2

= 18

2. Number of favourable outcomes white or blue 

= 5 white + 2 blue 

= 7

3. Probability = `"Number of favourable outcomes"/"Total number of outcomes"`

= `7/18`

The probability that the ball drawn is white or blue = `7/18`.