Question

A phone company offers two monthly plans. Plan A costs $20 plus an additional $0.12 for each minute of calls. Plan B has no initial fee but costs $0.16 for each minute of calls. For what amount of calling do the two plans cost the same? _minutes What is the cost when the two plans cost the same? $_

Answer 1

In this case, we'll have to carry out several steps to find the solution.

Step 01:

Data

Plan A

$20

$0.12 per minute

Plan B

$0

$0.16 per minute

Two plans cost the same:

time = ?

cost = ?

Step 02:

x = time (minutes)

y = cost ($)

Plan A

ya = 0.12x + 20

Plan B

yb = 0.16x + 0

Two plans cost the same: ya = yb

0.12x + 20 = 0.16x

20 = 0.16x - 0.12x

20 = 0.04x

20 / 0.04 = x

500 = x

yb = 0.16 * 500 = 80

The solution is:

The two plans cost the same when they reach 500min and the cost is $80.