Jason hired a luxury car service. The service charges a driver rate of $4.92, regardless of number of miles traveled, plus an additional $3.79 per mile. If Jason wants to spend no more than $4.20 per mile, what is the minimum number of mile should travel

Let's make two expressions.

4.92+3.79x

This represents the car service's cost, which x being miles.

4.2x

This is the most Jason wants to spend. Let's make them equal.

4.92+3.79x=4.2x

We need to get x by itself, Let subtract 3.79x from both sides.

4.92=0.41x

Let's divide.

4.92:0.41=12

So, he should not drive no more than 12 miles.