Question

A bag contains 6black,5blue,4pink balls.If 3 balls are drawn one by one with replecement,then what is the probability that all the balls are blue?

Answer 1

No. Of blue balls =5

No. Of black balls =6

. of Balls drawn=3

P(2 balls are blue & 1 ball is black)

=no. of possible ways of getting [2 balls are blue & 1 ball is black]/no. of possible ways of getting[3 Balls]

Now,

no. of possible ways of getting [2 balls are blue & 1 ball is black]

=(no. of possible ways of getting [2 balls are blue]) *( no. of possible ways of getting[1 ball is black])

=5C2 * 4C1

=10*4

=40

no. of possible ways of getting[3 Balls]

=9C3

=84

So,

P(2 balls are blue & 1 ball is black)

=40/84

=.47619

_____________

hope it helps !!☺☺