Mia buys 3 gallons of gas at d
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, or 3 * d =
3d.
The number
3 represents the quantity(how many) gallons she bought
The variable
d represents the rate at which Mia bought the gas.
Bob buys g gallons at 3
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, or 3 * g =
3g.
The variable
g number 3 represents the quantity(how many) gallons he bought
The number
3 represents the rate at which Mia bought the gas.