Question
7 topping how many different 2 topping can there be
Answers
Damon
combination of 7 toppings taken 2 at a time without regard for which is first
n!/[r!(n-r)!]
7!/[ 2! (5!) ]
7 * 6 /2
7 * 3
n!/[r!(n-r)!]
7!/[ 2! (5!) ]
7 * 6 /2
7 * 3