Algebra question

Question

A car rental company charges $.10 per mile plus $30 per day for a midsize sedan. If Lawrence rents a vehicle for four days and has $200, what is the maximum number of miles he can drive?

Answer 1

200 ≥ 0.1m + 30(4)

0.1m ≤ 80

d ≤ 800

 

He can drive a max of 800 miles.

Answer 2

Fear not! You can do this!

First, we need a formula:

We want to find the cost (C) if you travel a specific number of miles (m) and days (d). Each mile costs you the same $.10, and each day is another $30. That means you must multiply the mileage cost by the miles, and the daily cost by the days:

C    = .10m + 30d                    Since we know the final cost already, we substitute that:

200 = .10m + 30d                    We also know how many days Lawrence wants, so we insert that as well:

200 = .10m + 30(4)                  and simplify:

200 = .10m + 120                   Isolate the m by always doing the opposite, to whatever is furthest away on that side

-120             - 120

 

 

  80  = .10m                            and now divide by the last pest, the .10

 .10      .10                              resulting in...

 

 800 = m                                 So: he can drive up to 800  miles