Petrol Price Increase: 6.7% Drop in Mileage, 4.5% Increase in Cost

[chawki]

Homework Statement

After a rise in price of petrol, the driven mileage dropped by 6.7% , however the fuel costs increased by 4.5%.

Homework Equations

By what percentage did the petrol price rise ?

The Attempt at a Solution

isn't simply 4.5% ?

 

[Mark44]

Homework Statement

After a rise in price of petrol, the driven mileage dropped by 6.7% , however the fuel costs increased by 4.5%.

Homework Equations

By what percentage did the petrol price rise ?

The Attempt at a Solution

isn't simply 4.5% ?

No. You are ignoring the given information that the number of miles driven decreased by 6.7%. The fuel costs include the fact that fewer miles were driven. Since fewer miles were driven, the number of gallons of gasoline used decreased, but even so, the total spent on fuel increased.