#### Answer

$\frac{x}{7}$ + $\frac{x}{8}$ = 12

#### Work Step by Step

The sum of $\frac{1}{7}$ of a number and $\frac{1}{8}$ of that number gives 12.
let the number be x
" $\frac{1}{7}$ of a number" = $\frac{1}{7}$x = $\frac{x}{7}$
"$\frac{1}{8}$ of that number" = $\frac{1}{8}$x = $\frac{x}{8}$
The sum of $\frac{1}{7}$ of a number and $\frac{1}{8}$ of that number = $\frac{1}{7}$x + $\frac{1}{8}$x
On the right hand side we have 12
$\frac{x}{7}$ + $\frac{x}{8}$ = 12