Question

One bag contains 4 white balls and 3 black balls and a second bag contains 3 white balls and 5 black balls. One ball is drawn from the first bag and placed unseen in the second bag

Answer 1

here 2 cases::

1) transferred ball is white

then choosing that white ball from 1st bag is 5/9

and now there are 8 white,9 black in 2nd bag

so prob of choosing white from 2nd is=(5/9)*(8/17)....(1)

2) let the ball transferred is black with prob 4/9

in the same way as above,, prob is (4/9)*(7/17).........(2)

reqd prob is (1)+(2)=4/9