Let's say John drove 2 miles. He had to pay the base fee of $18.99 and $.75(2) = $1.50, so he paid $20.49 total.
We are given his total, though, and asked to find the mileage.
18.99 + .75m = 199.74
-18.99 -18.99
.75m = 180.75
.75 .75
m = 241
So, John drove 241 miles.
Hope this helps!
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