Chapter 12.6, Problem 18P

Find the value of each expression.

${}_5{C}_2$

To determine

Find the value of each expression.

  $C{}_2$

Answer to Problem 18P

10

Explanation of Solution

Given:

The given expression is :

  $C{}_2$

Formula Used:

  $C{}_r=\frac{n!}{r!(n-r)!}$

Calculation:

  $C{}_2=\frac{5!}{2!(5-2)!}=\frac{5!}{2!\cdot 3!}=\frac{5\cdot 4\cdot 3\cdot 2\cdot 1}{2\cdot 1\cdot 3\cdot 2\cdot 1}=10$ .