Question

two years of local internet service cost $685 including the installation fee of $85 what is the monthly fee?

Answer 1

2 years is the same as 24 months, so the equation would be:
685 = 24x + 85, where x is the monthly fee.
600 = 24x
600/24 = x
x = 25
The monthly fee is $25.

Answer 2

$25. First you subtract $85 from $685. Then you divide $600 by 2 because of two years. Then divide $300 by 12, for 12 months. This equals $25.