the gasoline gauge on a van initially read 3/8 full. when 12 gallons were added to the tank, the gauge read 5/8 full. how many more gallons are needed to fill the tank?

Question

anonymous · Answer

Let $x$ be the size of the tank.  Can you create an equation based on the information given?

anonymous · Answer

We could write 3/8 of tank as  $\frac 3 8 x$ and 5/8 of tank as  $\frac 5 8 x$

anonymous · Answer

"3/8 full. when 12 gallons were added"  becomes  $\frac 3 8 x + 12$

anonymous · Answer

So our final equation is $$
\frac 3 8 x + 12 = \frac 5 8 x
$$

anonymous · Answer

So 2/8 of the tank was added and that was 12 gallons. 2/8 is 1/4. A quarter of the tank is 12 then the whole tank would be 48 right? So you'll need 36 more gallons.

goformit100 · Answer

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