Nola's car gets approximately 42 miles per gallon. She is planning to drive x miles with her friends

What's the question?

If this is the question: what expression represents the number of gallons of gas she should expect to buy?

Then the answer is;

42 miles per gallon

What about x miles?

That gives x times 1 gallon divide by 42 miles

Which equals x/42 gallons.