Question 831724
Needed numbers are fuel efficiency in miles per gallon, and price of gasoline in dollars per gallon.


Let q be fuel efficiency, and let p be fuel price.
Sharon will do a round trip, so this is 2*180 miles.


{{{2*180(miles)(1/q)(gallons/mile)p(dollars/gallon)}}}, showing all the units with their numbers.
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{{{(2*180*p/q)*(miles)(gallons/miles)(dollars/gallons)}}}, showing all the units AFTER the number expression.
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Just compute, and notice how the units cancel to leave just dollars.