Based on the cost of the Verizon and AT&T plans, the number of months it will take till they are the same is 25 months.
First find out the difference between the monthly payments of both plans:
= 70 - 50
= $20
You would be paying $20 more per month with Verizon. This is the amount that would then pay for the phone.
The number of months it would take to do so is:
= 500 / 20
= 25 months
In conclusion, it will take 25 months for the cost to be the sane.
Find out more about comparing costs at https://brainly.com/question/1230252.