SOLUTION: Your car has a 12 gallon gas tank. you start off your week with a full tank. during the week you drive 145 miles. on Saturday you decide to take a road trip so you add 6 gallons of

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Question 1090786: Your car has a 12 gallon gas tank. you start off your week with a full tank. during the week you drive 145 miles. on Saturday you decide to take a road trip so you add 6 gallons of gas to your tank and leave town. you drive for 185 miles and your gas gauge reads exactly 1/4 full. what is your average gas mileage in miles per gallon?
Answer by ikleyn(52784) About Me  (Show Source):
You can put this solution on YOUR website!
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Your car has a 12 gallon gas tank. you start off your week with a full tank. during the week you drive 145 miles.
on Saturday you decide to take a road trip so you add 6 gallons of gas to your tank and leave town.
you drive for 185 miles and your gas gauge reads exactly 1/4 full. what is your average gas mileage in miles per gallon?
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Instead of solving for the ratio  miles%2Fgallon  I will solve the problem for the reciprocal ratio  gallons%2Fmile.
Then I will convert my answer to miles per gallon.

So, let x be the unknown ratio gallons-per-mile.

The full distance traveled is 145 + 185 miles = 330 miles.

The amount of the fuel spent is  12+%2B+6+-+%281%2F4%29%2A12 = 12 + 6 - 3 = 15 gallons.

    Notice that %281%2F4%29%2A12 is the volume of the gas that left in the tank.


From the other side, the amount of the fuel spent is  330*x gallons


It gives you an equation

15 = 330x.


Hence,  x = 15%2F330 = 1%2F22  gallon%2Fmiles.


Therefore, the answer to the problem's question is  22 miles per gallon.

Solved.