Question

Norma earns $22 per hour. She donates 5% of her wages to her favorite charity. If she wants to have at least $748 left after her donation, how many hours (H) must she work? (Round the number of hours up to the next whole hour.)

Answer 1

She must work for at least 36 hours

Explanation:

* Lets explain how to solve the problem

- Norma earns $22 per hour

- She donates 5% of her wages to her favorite charity

- She wants to have at least $748 left after her donation

- We want to find how many hours (H) she must work to have

this amount

- Assume that she will work for H hours

∵ She earns $22 per hour

∴ Her wages = 22 × H = 22H

- She donates 5% of her wage

∴ Her donate =
`(5)/(100)(22H)=1.1H`

- She wants to have at least $748 left after her donation

∵ The money left = her wage - her donate

∴ The money left = 22H - 1.1H = 20.9H

- She wants to have at least $748

∵ The money left ≥ $748

∴ 20.9H ≥ 748

- Divide both sides by 20.9

∴ H ≥ 35.789

∴ She must work for at least 36 hours