Question

Tim must choose 4 graphic novels out of a collection of 13 to take on vacation.

In how many ways can he select the graphic novels?

A. 28,561

B. 17,160

C. 715

D. 52

Answer 1

`C(13,4)=(13!)/(4!9!)=(10\cdot11\cdot12\cdot13)/(2\cdot3\cdot4)=715`

Answer 2

there are 715 ways to choose (C, 715)