# Liz earns a salary of $2,100 per month, plus a commission of 5% of her sales. She wants to earn at least$2,400 this month. How do you write an inequality to find amounts of sales that will meet her goal?

Jun 6, 2017

See a solution process below:

#### Explanation:

The expression to calculate Liz' earnings is:

$b + \left(c \cdot s\right)$

Where:

$b$ is the base salary. $2,100 for this problem. $c$is the commission rate: 5% for this problem. "Percent" or "%" means "out of 100" or "per 100", Therefore 5% can be written as $\frac{5}{100}$. $s$is the sales the commission rate is applied against. What we would solve for. If Liz wants her earnings to be at least$2,400 this would indicate a greater than or equal to inequality, or, $\textcolor{red}{\ge}$

We now have the information to write the inequality as:

$2,100 + (5/100 * s) >=$2,400

$2,100 + (5s)/100 >=$2,400