Combinations and Permutations
Permutation and combination related questions are common in PSC and Bank exams.
Before going to Combinations and Permutations, first lean about factorial. .
If \'n\' is a positive integer then, factorial of n is denoted as n! . .
5! = ( 1 x 2 x 3 x 4 x 5 ) = 120.
4! = (1 x 2 x 3 x 4 ) = 24.
Permutations are for lists of items, whose order matters and combinations are for group of items where order doesn’t matter. in other words, .
When the order of items doesn\'t matter, it is called as Combination.
When the order of items does matter it is called as Permutation.
The number of permutations of n objects taken r at a time is determined by using this formula:.
Permutation : Listing your 3 favourite football team in order, from list of...