printer and pages

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printer and pages

by ace_gre » Mon Jan 25, 2010 5:19 pm
It takes printer A 4 more minutes than printer B to print 40 pages. Working together, the two printers can print 50 pages in 6 minutes. How long will it take printer A to print 80 pages?
A) 12
B) 18
C) 20
D) 24
E) 30

I do not have the OA. Hope someone can help solve this. Thanks!

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by DeepakR » Mon Jan 25, 2010 5:41 pm
I used back solving and it took sometime..if there is any other easier approach please let me know.

Tried with D.)24

A takes 24 min to print 80 pages
Hence A will take 12 min to print 40 pages. So B would have taken 8 min to print 40 pages (from the info given)

Ra (Rate of A)=40/12 (pages/min).
Rb(Rate of B)=40/8=5(pages/min).

In 1 minute both A & B together would have done (40/12 +5) pages= 100/12 pages.
Hence in 6 minutes A & B together would have done = 100/12 * 6 = 50 pages (which matches the information given in the question).

OA is D=24

-Deepak

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by thephoenix » Mon Jan 25, 2010 8:41 pm
i solved using matrix method of MGMAT
CHECK THE ATT
Attachments
rate.xls
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by DeepakR » Tue Jan 26, 2010 1:53 am
Thank you !! that is the easiest approach..

-Deepak