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A phone company offers two monthly plans. Plan A costs $10 plus an additional $0.15 for each minute of calls. Plan B costs $30 plus an additional $0.10 for each minute of calls.

what amount of calling would the plans be the same?

WHAT IS THE COST WHEN 2 PLANS ARE THE SAME?

User Carleton
by
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1 Answer

2 votes

First, you need to write to expressions to model each situation:

Plan A: 10+0.15x

Plan B: 30+0.1x


Next, set the expressions equal to each other and solve for x:

10+0.15x=30+0.1x

*Subtract 0.1x from both sides to isolate the variable*

10+0.05x=30

*Subtract 10 from both sides*

0.05x=20

*Divide both sides by 0.05*

x=400


The plans would have the same cost after 400 minutes of calls.


To find how much money the plans cost at 400 minutes, plug 400 into either expression. We'll use Plan A:

10+0.15(400)

10+60

70


The plans will cost $70.


Hope this helps!

User Sfs
by
5.8k points