Question

Two competing cell phone companies have recently restructured their payment plans. Mobilama requires a $20 activation fee and charges $25 per month for their basic plan. Ringit Wireless requires no activation fee and charges $35 per month for their basic plan. When will the two plans be equal in cost?

Answer 1

At 2 months

Explanation:

25x+20=35x --> slove for x --> x=2

Answer 2

add 20$ and 25$ and go along the line while adding 25 each time, at the same time do the same for 35$, the answer is the second month