Evaluate the expression
-${ }_{9} \mathrm{C}_{5}$
A) 3024
B) 15,120
C) 126
D) 181,440

Question

Quizplus · Accepted Answer

${ }_{9} \mathrm{C}_{5}$ calculates the number of combinations of 9 items taken 5 at a time. The formula for combinations is ${ }_{n} \mathrm{C}_{r} = \frac{n!}{r!(n-r)!}$. Plugging in 9 for $n$ and 5 for $r$, we get ${ }_{9} \mathrm{C}_{5} = \frac{9!}{5!(9-5)!} = \frac{9!}{5!4!} = \frac{362,880}{120 \times 24} = \frac{362,880}{2,880} = 126$.

Evaluate the Expression - 9C5{ }_{9} \mathrm{C}_{5}9​C5​ A) 3024 B) 15,120 C) 126 D) 181,440

Evaluate the Expression
- ${ }_{9} \mathrm{C}_{5}$ A) 3024
B) 15,120
C) 126
D) 181,440