One cellular phone carrier charges $26.50 a month and $0.15 a minute for local calls. Another carrier charges $14.50 a month and $0.25 per minute for local calls. For how many minutes is the cost of the plans the same?

Answer 1

difference is 12 dollars per month
so for them to be the same the 0.15 needs to catch up to 0.25 by 12 dollars
12 / 0.25-0.15 = 12 / 0.1 = 120 minutes