Question

Kini earns 9 dollars an hour at her job and her allowance is 8 dollars per week. Duke earns 7.50 dollars an hour and his allowance is 16 dollars per week. How many hours do kini and duke need to work in order to save the same amount of money in one week.

Answer 1

5.3hrs or 5hrs 18mins

Explanation:

First, we have to put the information given to us about the money they earn into an expression

Let x represent the number of hours Kini and Duke work and y represent the total amount of money they earn in a week.

y(kini) = 9x + 8

y(duke) = 7.5x + 16

Now we subtract the x values and the constant values

9x - 7.5x = 1.5x

16 - 8 = 8

Make these into an equation

1.5x = 8

Divide both sides by 1.5 so x(the number of hours the both work) can stand alone.

`(1.5x)/(1.5) =(8)/(1.5)`

x = 5.3hrs or 5hrs and 18 mins

Answer 2

Explanation:

y = 9x + 8

y = 7.5x + 16

1.5x = 8

x = 5.3 hours