Question

A bag contains 8 red and 5 white balls.Three balls are drawn at random. Find the probability that one ball is red and two balls are white

Answer 1

Step 1:

Given a bag contains 8 red and 5 white balls

∴ The sample space is S=13(8+5)

Step 2:

One ball is red and two balls are white

Three cases arise in this situation

Case I:

If red balls is drawn at first position and then the white balls

Step 3:

Case II:

If red ball is drawn at second position and then the white balls correspondingly.

Step 4:

Case III:

If red ball is drawn at third position

Step 5:

P[one ball is red and two balls are white]