Question :

There are two small boxes A and B . In A there are 9 white beads and 8 black beads. In B there are 7 white and 8 black beads. We want to take a bead from a box. (a) What is the probability of getting a white bead from each box? (b) A white bead and a black bead are added to box B an then a bead is taken from it. What is probability of getting a white bead from it.
Submitted on 4/2/2024 | Answered by Vandana Rana

Answer :

Total number of beads in box A
=9W+8B = 17


Total number of beads in box
B =7W +8B= 15





(a) P(getting a white bead from box A) =
9/17

P(getting a white bead from box B) =
7/15


(b) When a white bead and a black bead are added to box B,

Number of white beads in box
B = 7W+1W

=8W


Number of black beads in box B
=8B +1B

= 9B


Thus, total number of beads in box
B =8W +9B

= 17


Hence, P(getting a white bead from box B) = 8/17