Question 141

A bag contains 7 blue balls and 5 yellow balls. If two balls are selected at random, one by one without replacement. What is the probability that none of the selected ball is yellow?

Solution

The probability that the first ball is not yellow is $$\frac{7}{12}$$
The probability that the second ball is not yellow is $$\frac{6}{11}$$
Hence, the total probability is $$\frac{7}{12}*\frac{6}{11}=\frac{7}{22}$$

Video Solution

video

Create a FREE account and get:

  • Download Maths Shortcuts PDF
  • Get 300+ previous papers with solutions PDF
  • 500+ Online Tests for Free