Chapter 8, Problem 16CT

To determine

To evaluate the below expression−

  $C{}_3$

Answer to Problem 16CT

Thesolution is $84$ .

Explanation of Solution

Given: Expression: $C{}_3$

Formula Used:

  $C{}_r=\frac{n!}{\left[r!\left(n-r\right)!\right]}$

Calculation:

Given: Expression: $C{}_3$

Using above formula, we have:

  $\begin{array}{l}C{}_3=\frac{9!}{3!\left(9-3\right)!}\\ C{}_3=\frac{9\times 8\times 7\times 6!}{3\times 2\times 6!}\\ C{}_3=84\end{array}$

Conclusion:

Hence, the solution is $84$ .