#### Answer

$\frac{x}{9}$ + $\frac{x}{10}$ = 15

#### Work Step by Step

The sum of $\frac{1}{9}$ of a number and $\frac{1}{10}$ of that number gives 15.
let the number be x
" $\frac{1}{9}$ of a number" = $\frac{1}{9}$x = $\frac{x}{9}$
"$\frac{1}{10}$ of that number" = $\frac{1}{10}$x = $\frac{x}{10}$
The sum of $\frac{1}{9}$ of a number and $\frac{1}{10}$ of that number = $\frac{x}{9}$ + $\frac{x}{10}$
On the right hand side we have 15
$\frac{x}{9}$ + $\frac{x}{10}$ = 15