Answer
$105$
Work Step by Step
Binomial Coefficient can be defined as:
$\displaystyle \binom{n}{k}=\dfrac{n!}{k!(n-k)!}$
Need to apply the formula to get the Binomial Coefficients.
Here, $n=7,k=2$
Therefore,
$\displaystyle \binom{15}{2}=\dfrac{15!}{2!(15-2)!}$
$=\dfrac{ 15 \cdot 14 \cdot 13!}{(2 \cdot 1)(13!)}$ $\bf{(Simplify)}$
$=105$
