Answer
$\$2000$.
Work Step by Step
Let the total sales $=x$.
$5\%$ commission on sales $=0.05x$.
$15\%$ commission on sales $=0.15x$.
First salary $=200+0.05x$
Second salary $=0.15x$
Equate both salaries.
$\Rightarrow 0.15x=200+0.05x$
Subtract $0.05x$ from both sides.
$\Rightarrow 0.15x-0.05x=200+0.05x-0.05x$
Add like terms.
$\Rightarrow 0.10x=200$
Divide both sides by $0.10$.
$\Rightarrow \frac{0.10x}{0.10}=\frac{200}{0.10}$
Simplify.
$\Rightarrow x=2000$
Hence, the earnings be the same at $\$2000$ sales.
