best method?

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best method?

by mehaksal » Wed Aug 29, 2012 10:17 am
The telephone company wants to add an area code composed of 2 letters to every phone number. In order to do so, the company chose a special sign language containing 124 different signs. If the company used 122 of the signs fully and two remained unused, how many additional area codes can be created if the company uses all 124 signs?

a) 246
b) 248
c) 492
d) 15,128
e) 30,256

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by js0704 » Wed Aug 29, 2012 12:25 pm
124^2-122^2 = ?

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by Anurag@Gurome » Wed Aug 29, 2012 10:04 pm
mehaksal wrote:The telephone company wants to add an area code composed of 2 letters to every phone number. In order to do so, the company chose a special sign language containing 124 different signs. If the company used 122 of the signs fully and two remained unused, how many additional area codes can be created if the company uses all 124 signs?

a) 246
b) 248
c) 492
d) 15,128
e) 30,256
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by LalaB » Wed Aug 29, 2012 11:32 pm
Oh God, all questions posted by you are already discussed trillion times.all reasonable and unreasonable methods are also there.
why dont u try to use google? no need to invent a bike. everything has been already done
if after google-ing and reading that trillion posts , u still have question(hm, is it possible?!), u can easily post ur question in the same topic. no need to double/ triple all these questions

remember in the gmat study quality > quantity.
sorry, if I were rude, but I really hope u will take a minute to think about quality and quantity matters.dont waste ur precious time on unnecessary things

anyways, u r the only one who makes decisions. so, u can ignore my words :)
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