Question

One cell phone plan charges $20 per month plus $.15 per minute used. A second cell phone plan charges $35 per month plus $.10 per minute used. Write and solve an equation to find the number of minutes you must talk to have the same cost for both calling plans.

Answer 1

20+0.15x = 35+0.10x

0.15x=15+0.10x

0.05x=15

x= 15/0.05

x= 300minutes

check:

300*.015 = 45+20=65

300*0.10 = 30 + 35 = 65

they equal

 so number of minutes would be 300