Sorry to bother you all with what might seem like a simple conversion problem, but I have tons of HW to do, and math is absolutely NOT my area of expertise. So, have at it, you math-wizards.

A full explanation would be greatly appreciated, too.

In 2012, Germans paid 1.65 Euros per liter of Gasoline. At the same time, American prices were $3.90 per gallon.

a. How much would one gallon of European gas have cost in dollars?
b. How much would one liter of American gasoline have cost in Euros?
(one US = 0.76 Euros, 1 gallon = 3.78)

First, start by transferring a liter to a gallon. 3.78 liters in 1 gallon.
This means they pay 1.65*3.78=6.24 euros per gallon of gasoline. If the conversion is 1 us dollar = .76 euros, set up a proportion where x$=6.24euros.... .76x=6.24.... x=$8.21

Next, do the reverse. One liter is .26 gallons, meaning we pay 3.90*.26=$1.01 for a liter of gas. Convert this back into euros by multiplying it by .76... 0.77 Euros

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