The expression represents the number of gallons used is m/22.
Given
Nikki can drive her car 22 miles on each gallon of gasoline.
<h3>What is the unit rate?</h3>A rate is a ratio that is used for comparing two different kinds of quantities which have different units.
To find the number of gallons used we will divide the total distance traveled by distance traveled in one gallon.
Therefore,
If Nikki drives m miles, the expression represents the number of gallons used is;
Hence, the expression represents the number of gallons used is m/22.
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