Question

How many ways can 8 cards be selected from a pile of 12 cards?

Answer 1

No. of ways`=""_12C_8=(12!)/((12-8)!8!)=(12!)/(8!4!)`

`=(cancel(8!)*9*10*11*cancel(12))/(cancel(8!)*1*2*cancel(3*4))=9*5*11=495`.