Question

Renting video games from The Video Vendor costs

6 dollars per game with no annual membership fee.

Renting video games from the Game Garage

costs 3 dollars per game, but a customer must

pay an additional $60 for an annual membership.

If n represents the number of video games a

customer rents in a year, which of the following

gives all values of n for which it costs less to rent

from the Game Garage than from the Video

Vendor?

The options are (a) n < 10, (b) n = 10, (c) 10 < n < 20, (d) n = 20, (e) n > 20

Answer 1

So a good starting point for this one is to ask, what is the break even point?

Answer 2

To find the break even point you need to look at this problem as a simultaneous equation.

Answer 3

The easiest way to solve a simple simultaneous equation like this is to equate both equations and solve for x.
For instance: Video Vender cost function = Game Garage cost function (where for each of these functions, x represents the number of videos per yer.
Solving for x gives the break even point (you can also visualize this as being the point where the 2 functions intersect if you were to graph them together).
Once you have this 'break even' point, the answer should be obvious.