Find the number of ways in which two small squares can be selected on the normal chessboard if they are not in same row or same column.

Answer

1568

Explanation

First square can be selected in 64 ways. Second square can be selected in 65-15=49 ways.
But when first square, say c3 is selected, sometimes g5 is selected as second square.
Similary, when first square, say g5 is selected, sometimes c3 is selected as second square. Thus, each paris is selected twice. So, the total number of ways is `64xx49//2=1568`