Question

The telephone company offers two billing plans for local calls. Plan 1 charges ​$27 per month for unlimited calls and Plan 2 charges ​$11 per month plus ​$0.05 per call. A. Use an inequality to find the number of monthly calls for which Plan 1 is more economical than Plan 2.

Answer 1

0.05x+11<27 for x<=320

Explanation:

Step one:

Plan 1

charges = $27 monthly

the total charges is expressed as

y=27------1

Plan 2

charges= $11 monthly

extral= $0.05 per call

let x be the number of calls

the total is expressed linearly as

y=0.05x+11--------2

Step two:

equating 12 and 2 we have

27=0.05x+11

collect like terms

27-11=0.05x

16=0.05x

divide both sides by 0.05

x=16/0.05

x=320

the inequality for which plan A is more economical is

0.05x+11<27 for x<=320