Jane drives from City A to City B, a distance of 180 miles. Her car consumes fuel at a rate of 30 miles per gallon. On the return trip from City B to City A, she encounters heavy traffic and her fuel efficiency drops to 24 miles per gallon. If the fuel price is $3 per gallon, calculate the total fuel cost for the round trip. Let's think step by step and output the final answer within \boxed{}.
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