Question

Janine worked 15 hours last weel. One job as a clerk in a sporting goods store pais her $8.47 per hour, while her jo giving piano lessons paid $17 per hour. If she earned $178.23 between the two jobs, how many hours did she work at each job?

Answer 1

She worked 9 hours on store and gave piano lessons for 6 hours

Explanation:

Let x be the no. of hours she worked on store

Cost of 1 hour on shop = $8.47

Cost of x hours on shop = $8.47x

Let y be the no. of hours she gave piano lessons

Cost of 1 hour for piano lessons = $17

Cost of y hours on shop = $17y

Now we are given that She worked for 15 hours

So,
`x+y=15` ---1

We are also given that she earned $178.23 between the two jobs

So,
`8.47x+17y=178.23` --2

Plot equation 1 and 2 on graph

Refer the attached figure

`x+y=15` -- Blue line

`8.47x+17y=178.23` -- Green line

Intersection point gives the solution .

Intersection point = (9,6)

So, x = 9 and y = 6

So, she worked 9 hours on store and gave piano lessons for 6 hours