SOLUTION: A car's gas tank is 1/2 full. if eight gallons are added,the tank will become 7/8 full.what is the full capacity of the tank?

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Question 1013399: A car's gas tank is 1/2 full. if eight gallons are added,the tank will become 7/8 full.what is the full capacity of the tank?
Found 3 solutions by ikleyn, josgarithmetic, rafay10ashfaq@hotmail.com:
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
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A car's gas tank is 1/2 full. If eight gallons are added,
the tank will become 7/8 full. What is the full capacity of the tank?
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Let V be the tank volume (full capacity) in gallons.

Then, according to the condition,

V%2F2+%2B+8 = %287%2F8%29%2AV.

It is your equation to determine V. To solve it, multiply both sides by 8. You will get

4V + 64 = 7V,

64 = 7V - 4V,

64 = 3V,

V = 64%2F3 = 211%2F3 gallons.


Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
v, the volume capacity of the tank.

%28v%2F2%2B8%29%2Fv=7%2F8 for comparing the volume of fuel in the tank to the tank's capacity volume. Once this makes sense to you, just the arithmetic is still to be done.

v%2F2%2B8=%287%2F8%29v
%287%2F8%29v-v%2F2=8
%287%2F8-1%2F2%29v=8
%283%2F8%29v=8
v=64%2F3
highlight%28v=21%261%2F3%29

Answer by rafay10ashfaq@hotmail.com(1) About Me  (Show Source):
You can put this solution on YOUR website!
8 gallons fills 7/8-1/2 of the tank. This means that to fill 3/8 of the tank you need 8 gallons. To fill 1/8 of the tank, you need 1/3 as much gas, so 8/3 gallons. To fill 8/8 of the tank (the whole tank) you need 8/3*8 gallons, or 64/3 gallons.