Suppose Bella has already saved $60 and earns $15 per hour for summer job. Her boyfriend Edward has already saved $100, but only earns $10 per...

Hello!

We don't know how many hours they work a day, tberefore we can answer in terms of hours only. Also, i have to suppose that they work the same amount of hours.

"The same amount of money" may mean "the same for both persons" or "the same as needed for one iPod for both". Let's solve both variants.

1. Denote the number of hours when they will have the same amount of money as...

Hello!

We don't know how many hours they work a day, tberefore we can answer in terms of hours only. Also, i have to suppose that they work the same amount of hours.

"The same amount of money" may mean "the same for both persons" or "the same as needed for one iPod for both". Let's solve both variants.

1. Denote the number of hours when they will have the same amount of money as x. Then Bella will have 60+15x dollars and Edward will have 100+10x and these amounts were equal:

60+15x=100+10x.

Move 10x to the left and 60 to the right (changing the sign) and obtain

5x=40, or x=8 (hours).

So the answer is: they will have the same amount of money after 8 hours of simultaneous work.

2. In this case Bella again will have 60+15x dollars and Edward will have 100+10x dollars. They will have 60+15x+100+10x=25x+160 and this must be equal to 210.

25x+160=210 means 25x=210-160=50 or x=2 (hours).

For this problem the answer is: they will have enough money for one iPod after 2 hours of each person's work.