Question

Mary is paid $12 per hour at her weekend part-time job. She earns an average of $132 each weekend, but her earnings can vary by $36. Which inequality represents the number of hours, h, Mary could work in one weekend? A. h ≤ 8 or h ≥ 14 B. h ≤ 3 or h ≥ 11 C. 3 ≤ h ≤ 11 D. 8 ≤ h ≤ 14

Answer 1

Given:

Mary is paid $12 per hour at her weekend part-time job.

She earns an average of $132 each weekend, but her earnings can vary by $36.

To find:

The inequality for number of hours.

Solution:

Let h be the number of hours Mary could work in one weekend.

Total earning for h hours = $12h

She earns an average of $132 each weekend, but her earnings can vary by $36. So,

$132-36\leq \text{Total earning}\leq 132+36$

$96\leq \text{Total earning}\leq 168$

$96\leq 12h\leq 168$

Divide all sides by 12.

$\dfrac{96}{12}\leq \dfrac{12h}{12}\leq \dfrac{168}{12}$

$8\leq h\leq 14$

Therefore, the correct option is D.