SOLUTION: Any knows about this ? After a rise in price of petrol, the driven mileage dropped by 6.7% , however the fuel costs increased by 4.5%. By what percentage did the petrol price rise

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Question 388857: Any knows about this ?
After a rise in price of petrol, the driven mileage dropped by 6.7% , however the fuel costs increased by 4.5%. By what percentage did the petrol price rise ??
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
To compare price/gallon of petrol, You need too do so for
an equal number of miles driven, before and after the price
increase.
Before, the % ratio of costs to miles driven is 1%2F1
I can call it %281-.067%29%2F%281-.067%29+=+.933%2F.933
Afterwards, the cost to miles driven is .933+%2B+.045%29%2F.933+=+.978%2F.933
The % price rise is %28.978+-+.933%29%2A100+=+4.5
The price rose 4.5%