its very easy easy easy n intersting.......

Can somebody please explain this? Thanks gnenerally... 2 * 5 = 10 gives u a 0 (eg:6! contains 1 * 2 * 3 * 4 * 5 * 6 = 72 0 ) so u ve to find the no of (2 * 5) pairs in 60!. To find them ...first find the no of numbers dvisible by 5 in 60! ie.60/5 = 12 (this is because 60! = 1 * 2 * 3 *4 *5 * 6 .......