# Linda earns $40 base pay per week, plus 10% commission on all sales. What were her sales if she made$112 in one week?

Her sales for the week were $720 #### Explanation: The formula for total salary is: $T = b + r \cdot s$Where $T$is total salary, $b$is the base salary, $r$is the commission rate and $s$is the sales. "Percent" or "%" means "out of 100" or "per 100", Therefore 10% can be written as $\frac{x}{100}$. Given this we can substitute the values we know and solve for $s$while keeping the equation balanced: $112 = $40 + 10/100s $112 - 40 = $40 -$40 + 10/100s
$72 = 0 + 10/100s $72 = 10/100s
100/10 * $72 = 100/10 10/100s 10 *$72 = cancel(100)/cancel(10) cancel(10)/cancel(100)s
\$720 = s#