There are n white and n+1 black balls in urn A, there are n+1 white balls and n black balls in urn B. One ball is drawn from urn A and put into urn B. Then two balls are drawn from urn B and put into urn A. When the operation is completed, the probability that urn A contains same number of white and black balls is 1325. Then the number of balls in urn A at the start of the operation was

There are n white and n+1 black balls in urn A, there are n+1 white ba

1.	There are n white and n+1 black balls in urn A, there are n+1 white balls and n black balls in urn B. One ball is drawn from urn A and put into urn B. Then two balls are drawn from urn B and put into urn A. When the operation is completed, the probability that urn A contains same number of white and black balls is 1325. Then the number of balls in urn A at the start of the operation was
Answer» There are $n$ white and $n + 1$ black balls in urn $A$ , there are $n + 1$ white balls and $n$ black balls in urn $B$ . One ball is drawn from urn $A$ and put into urn $B$ . Then two balls are drawn from urn $B$ and put into urn $A$ . When the operation is completed, the probability that urn $A$ contains same number of white and black balls is $\frac{13}{25}$ . Then the number of balls in urn $A$ at the start of the operation was