By lowering the temperature of their electric hotwater heater from 140 degrees fahrenheit to 120 degrees fahrenheit, the Kellys' average electric bill dropped by 7% to $60.45. What was their electric bill before they lowered the temperature of their hot water?
If anyone can show me how to do this problem, that'd be amazing.
2006-12-11 13:19:40 · 6 answers · asked by Danielle 2 in Science & Mathematics ➔ Mathematics
If b is the original amount of the bill, 0.93b is what it is after dropping 7% because 100% - 7% is 93% and 93% as a decimal is 0.93
Anyway, 0.93b = 60.45
Divide by 0.93 to get b
Hope that makes sense
2006-12-11 13:23:55 · answer #1 · answered by hayharbr 7 · 0⤊ 0⤋
the prevoius bill was $65. heres how u do it. let us assume the previous bill was x. then the bill dropped by 7% to $60.45. therefore 93% of x =60.45. 93/100*x=60.45.
x=60.45*100/93. solve this u will get x=65.
2006-12-11 21:26:16 · answer #2 · answered by SRM 1 · 0⤊ 0⤋
Since their bill dropped 7%, 93% is left so $60.45 is 93% of the original or
.93x=60.45
x=60.45/.93=$65.00
2006-12-11 21:23:11 · answer #3 · answered by yupchagee 7 · 0⤊ 0⤋
.93x=60.45<--93 percent (what is left) of previous bill = $60.45
x=65<---divide both sides by .93---previous bill= $65.00
2006-12-11 21:26:24 · answer #4 · answered by d.treadway 2 · 0⤊ 0⤋
65 x 0.07 = 4.55
65-4.55 = 60.45
original bill is 65 dollars.
2006-12-11 21:23:32 · answer #5 · answered by Anonymous · 0⤊ 0⤋
let x = the original electric bill average.
x - 0.07x = 60.45
combine like terms
1.07x = 60.45
/1.07 = /1.07
x = 60.45/1.07
I will let you take it from here.
2006-12-11 21:30:48 · answer #6 · answered by ikeman32 6 · 0⤊ 0⤋