<PRE><B>Question 1188857</B>
the cost is 60 dollars a week plus .75 per mile.
max you can spend is 210.
formula is c = 60 + .75*x
c is the cost
60 is the fixed part of the cost.
.75 * x is the variable part of the cost.
when c = 120, the formula becomes:
210 = 60 + .75 * x
subtract 60 from both sides of the equation to get:
150 = .75 * x
divide both sides by .75 to get:
150 / .75 = x
solve for x to get:
x = 200.
you can drive 200 miles each week if the most you have to spend is 210 dollars.
this assumes the tax is included as part of the cost, which is not usually the case.
c = 60 + .75 * 200 = 210, confirming the solution is good.




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