Let x represent the number of months it will take for the cost of both plans to be the same.
For the first plan, it requires a $80 sign up fee and costs $20 per month. Thus, the cost of using this plan for x months would be
20x + 80
For the second plan, it requires a $70 sign up fee and costs $25 per month. Thus, the cost of using this plan for x months would be
25x + 70
For both costs to be the same, it means that
25x + 70 = 20x + 80
25x - 20x = 80 - 70
5x = 10
x = 10/2
x = 5
After 2 months, the cost of both plans would be thesame
The cost would be
25 * 2 + 70
= 50 + 70
= 120
The cost would be $1207
