Phone plan

[Thonk02]

I have looked at this problem a million times and dont see how to get this answer.

Phone Company X has plan A and Plan B. Plan is is 0.60 cents per minute for the first 7 minutes and .06 cents per minute every minute afterwards. Plan B is .08 cents per minute fro all minutes. In minutes, when will plan A and plan B cost the same.

A. 7
B. 8
C. 9
D. 21
E. 30

Answer is C. Am i missing something here??

[shibal]

In this cases i'd rather do backsolving, much easier and faster.... By setting up the equation u'll lose at least 40 sec...

[Thonk02]

Yea but even using the answer, i dont get the same amount. using nine minutes I get $4.32 for Plan A and .72 cents for Plan B. Is this question jsut a typo....it was on the GMAC practice exam.

[typhoonguywlblwu]

let x be the number of minutes.
Using Plan A
.6+(x-7).06 = total cost.

Using Plan B
.08x = total cost.since they are same,
.6+(x-7).06 = .08x
.6+.06x-.42 = .08x
or .18 = .02x therefore x=.18/.02 = 18/2 = 9 ans.

The possible mistake you could be making is computing the cost of plan A as .6+(x-1).06 but the cost of whole 7 minutes is .6 and not for the first minute.



Hope it helps.

[anabbasi]

Shouldn't the total cost using Plan A be

.6(7)+(x-7).06
because the question says

Plan A is is 0.60 cents PER MINUTE for the first 7 minutes and .06 cents per minute every minute afterwards

it says per minute

[cata1yst]

I have looked at this problem a million times and dont see how to get this answer.

Phone Company X has plan A and Plan B. Plan is is 0.60 cents per minute for the first 7 minutes and .06 cents per minute every minute afterwards. Plan B is .08 cents per minute fro all minutes. In minutes, when will plan A and plan B cost the same.

A. 7
B. 8
C. 9
D. 21
E. 30

Answer is C. Am i missing something here??

You copied the problem wrong. It is supposed to be ".60 for the FIRST 7 minutes of each call..."

Hence...why you can't come up with 9 as your answer.

[xilef]

According to the problem , the correct equation is:

7(.6)+(x-7)(.06)=x(.08)

there must be some kind of a typo in the problem.

[xilef]

I have looked at this problem a million times and dont see how to get this answer.

Phone Company X has plan A and Plan B. Plan is is 0.60 cents per minute for the first 7 minutes and .06 cents per minute every minute afterwards. Plan B is .08 cents per minute fro all minutes. In minutes, when will plan A and plan B cost the same.

A. 7
B. 8
C. 9
D. 21
E. 30

Answer is C. Am i missing something here??

You copied the problem wrong. It is supposed to be ".60 for the FIRST 7 minutes of each call..."

Hence...why you can't come up with 9 as your answer.

good, then 9 is the OA