# To join a gym, you pay a one-time fee of $75 and $45 per month for the duration of the membership. You have paid a total of $345. How long have you been a member of the gym?

##### 1 Answer

Oct 22, 2016

You have been a member for 6 months.

#### Explanation:

Let

The total variable cost is

The fixed cost is $75.

The total cost is then

Then the equation will be