Previous Year Paper
CAT-2002-Previous Years Paper
In how many ways is it possible to choose a white square and a black square on a chessboard so that the squares must not lie in the same row or column?
A black square can be chosen in 32 ways. Once a black square is there, you cannot choose the 8 white squares in its row or column. So the number of white squares available = 24
Number of ways = 32 × 24 = 768