Question

A bag contains 6 white & 4 black balls. Two balls are drawn at random. The probability that are of the same colour is

Answer 1

Step-by-step explanation:

one can select 2 white or 2 black balls in which cases they will be of the same color.

There are 6 white + 4 black balls = 10 balls.

so, in 10c2 ways, 2 balls can be selected from the 10 balls.

number of selecting 2 white ball =6c2.

therefore, the probability of selecting 2 white balls = 6c2/10c2.

number of ways of selecting 2 blacks balls=4c2.

therefore, the probability of of selecting 2 black balls = 4c2/ 10c2 .

therefore, the probability of selecting two balls of same color = (6c2+4c2)/10c2.

=(15+6)/45

= 21/45

= 7/15.