Final answer:
To find the cost per gallon, divide the total cost by the number of gallons purchased.
Step-by-step explanation:
To find the cost per gallon, you need to divide the total cost by the number of gallons. In this case, you bought 15 gallons of gas for $60. So, the cost per gallon would be $60 divided by 15, which equals $4 per gallon.
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