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2020 AMC 12A Problem 3

Problem 3 of 25EasierArithmetic

A driver travels for 22 hours at 6060 miles per hour, during which her car gets 3030 miles per gallon of gasoline. She is paid $0.50\$0.50 per mile, and her only expense is gasoline at $2.00\$2.00 per gallon. What is her net rate of pay, in dollars per hour, after this expense?

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Solution

In 22 hours she drives 120120 miles, earning 120⋅$0.50=$60.120 \cdot \$0.50 = \$60. She uses 120÷30=4120 \div 30 = 4 gallons, costing 4⋅$2.00=$8.4 \cdot \$2.00 = \$8. Her net earnings are $60−$8=$52,\$60 - \$8 = \$52, so her rate is $52÷2=$26\$52 \div 2 = \$26 per hour. Thus, E is the correct answer.
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