Two years of local Internet service costs $685, including the installation fee of $85. What is the monthly fee?

Question

Well I know the concept of this topic I am doing but, I do not understand how to make word problems into a equation.

Answer 1

Nicole, 

 

A key ingredient of success at working with word problems is defining units correctly.  In this case, note that the cost corresponds to 2 years of service.  Also, the problem asks for the one-month fee.  Then, a good start would be saying: OK, the cost of 24 months of service was $685, including the installation fee. Since this fee is a one-time cost, not a monthly cost, we need to subtract it from our total cost. Then the cost of the service minus the installation fee could be written as:

 

24x = 685 - 85

 

That is: 24 months of service, at x cost per month, is equal to 685 minus 85. 

 

If you solve this equation, you will find the value of x:

 

24x = 600 

 

x = 600 ÷ 24

 

x = 25

 

The monthly fee is $25.  In 2 years you paid 24 times 25, or $600.  Add to this amount the installation fee of $85 and you will arrive to your total cost, which includes the installation fee.