Question 498262: kelly earns 40% more than her sister, and together they earn $720 per week. How much does kelly earn per week? Answer by Maths68(1474) (Show Source):
You can put this solution on YOUR website! Let Kelly's sister earns = x
Kelly earns = (x*40%)+x
Kelly earns = x*(40/100)+x
Kelly earns = x*(2/5)+x
Kelly earns = (2x/5)+x
Together both earns = 720
x+(2x/5)+x=720
2x+(2x/5)=720
Multiply by 5 both sides
10x+2x=3600
12x=3600
Divide by 12 both sides
12x/12=3600/12
x=300
Kelly's sister earns = 300$
Kelly earns = x*(2/5)+ x
Put the value of x in above equation
Kelly earns = 300*(2/5)+300
Kelly earns = 60*(2)+300
Kelly earns = 120+300
Kelly earns = 420$
