Question

Find the value of $n$ if
$\frac{1}{8!}+\frac{1}{9!}=\frac{n}{10!}$

Answer 1

$\frac{1}{8!}+\frac{1}{9!}=\frac{9}{9!}+\frac{1}{9!}=\frac{10}{9!}$

$=\frac{10\times 10}{10!}$

$\frac{100}{10!}$ $\therefore n=100$