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If I drove $38.91$ miles, and my car gets $22$ miles to the gallon, and gas cost $ $3.699$ per gallon, how much did I spend on gas?

I'm sure this is an algebra problem, but I can't think where to put the X to my equation to try and figure this out

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Never mind! I can't see how to unpost this, so instead, I'll share what just dawned on me, since I apparently had a case on "brain blank" If 22 miles = 1 gallon, and I drove 38.91 miles, then 38.91 / 22 = 1.769 1.769 x $3.699 per gallon = $6.54 So I spent about $6.54 on gas Thank You All Anyway! – Kelly B Sep 5 '12 at 1:10
There should be a series of links "share edit close delete flag" at the bottom of the question. The one you want is "delete". Congratulations on solving your own problem! – MJD Sep 5 '12 at 1:35
Kelly, you can write it up as an answer, then later you can accept it, if you want to. – Gerry Myerson Sep 5 '12 at 1:38

I would recommend learning to set up problems in a clear and concise way.

For example:

Distance = D = 38.91 Miles

Gallons per Mile = G = 22 Miles / Gallon

Cost Gas = C = 3.699 Dollars / Gallon

Now, how would you describe in words how to calculate how many Gallons you used?

Knowing that, how would you calculate your total cost?

I know this looks trivial, but trust me, it will be a huge help in the future with easy and much harder problems!


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The nice feature of this approach is that if you pay close and strict attention to units, understanding increases greatly. – Lubin Oct 5 '12 at 5:28

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