Lena wants to buy a computer that costs $900 dollars. she already. has $473 dollars saved. her grandmother will pay her $7 an hour to her with the yard work. how many hours will lena need to work before she can afford to buy the computer

If you would like to know how many hours will Lena need to work before she can afford to buy the computer, you can calculate this using the following steps:

$900 - $473 = $427

$427 / $7 = 61 hours of yard work

Result: Lena will need to work 61 hours before she can afford to buy the computer.

Cost of the computer that Lena wants to buy = 900
Amount of money saved by Lena = $473
Amount per hour paid by Lena's grandmother = $7
Let us assume the number of hours Lena have to work = x
Then
473 + 7x = 900
7x = 900 - 473
7x = 427
x = 427/7
  = 61
So Lena has to work 61 hours before she can afford top buy the computer.I hope the procedure is clear enough for you to understand.