Answer to Question #201175 in Combinatorics | Number Theory for Fatowore Samson

Question

4C2 is equal to _____________

Answer 1

We know that,

$$^nC_r=\dfrac{n!}{r!\cdot(n-r)!}$$

So,

$$^4C_2=\dfrac{4!}{2!\cdot (4-2)!}=\dfrac{4!}{2!\times2!~}=\dfrac{24}{4}=6$$

Hence,

$\boxed{^4C_2=6}$