If from each of the three boxes containing 3 white and 1 black, 2 white and 2 black, 1 white and 3 black balls, one ball is drawn at random, then the probability that 2 white and 1 black balls will be drawn, is

Options

A. `13//12`
B. `1//4`
C. `1//32`
D. `2//3`

Answer

A

Explanation

Given , Box (1) =3W, 1B, Box (II) =2W, 2B, Box (III) =1W, 3B.
`therefore` Required probability
`=P(BWW)+P(WBW)+P(WWB), `
`=P(B)P(W)P(W)+P(W)P(B)P(W)+P(W)P(W)P(W)`
`=1/4xx2/4xx1/4+2/4xx2/4xx1/4+3/4xx2/4xx3/4`
`=(2+6+18)/(64)=(26)/(64)=13/32`