Using Variables to Express Inequalities, Grade 7 Math *PLEASE HELP* (QUESTION 3)

Question

Alan earns $.7.50 per hour at his after-school jobs. He is saving money to buy a skateboard that costs $120. How many hours will he have to work to earn enough money for the skateboard?

Let h represent the number of hours Alan will have to work.

Inequality; ______________

Alan will have to work _________________________ hours.

Lesson 3.5, pg 49, question 3 of Grade 7 Spectrum Math

I am looking for answer + explanation.

Thank you!

Answer 1

In this question, $120 is the minimum amount of money Alan needs to make to buy a skateboard. The money that Alan would make depending on the number of hours he works would be written as “7.5h.” Since $120 is the minimum amount Alan needs to make, “7.5h” has to be greater than or equal to $120.

Inequality: 7.5h≥120

To find how many hours Alan has to work, you need to get “h” by itself. The first step is to divide both sides by 7.5.

7.5h/7.5≥120/7.5

h≥16

Alan will have to work 16 hours.

To check your work, substitute “h” in the original inequality for the answer you get (in this case, 16) to see if the inequality makes sense.

7.5(16)≥120

120≥120✔️