Question

A cell phone company offers two plans.

Plan A has a monthly fee of $26.50 and charges $0.35/minute.
Plan B has a monthly fee of $42.50 and charges $0.15/minute.
How many minutes make Plan A and Plan B equal to each other?

Answer 1

80 minutes

Explanation:

Represent Plan A as y = $26.50 + ($0.35/min)x, where x is the number of minutes consumed.

Represent Plan A as y = $42.50 + ($0.15/min)x

We set these two equations equal to one another and solve for x, the number of minutes at which the costs of the two plans are momentarily equal:

y = $26.50 + ($0.35/min)x = y = $42.50 + ($0.15/min)x

Combining like terms, we get: ($0.20/min)x = $16.00

$16.00

Then x = -------------------- = 80 minutes

($0.20/min)