Problem Solving

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!

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

i solved using matrix method of MGMAT
CHECK THE ATT

Thank you !! that is the easiest approach..

-Deepak