If two copying machines work simultaneously at their respective constant rates, how many copies do they produce in 5 minutes?
(1) One of the machines produces copies at the constant rate of 250 copies per minute.
(2) One of the machines produces copies at twice the constant rate of the other machine.
From (1):
It talks about only one machine. We dont know the rate of other machine to determine the answer. So, INSUFFICIENT
From (2):
Rate of machine A = 2 * Rate of machine B
or
Rate of machine B = 2 * Rate of machine A
But again, we dont know the exact rate to determine the answer of how many copies those machines produce. So, INSUFFICIENT
Now from (1) and (2), if both the machines work simultaneously, then in we know the number of copies they produce in one minute which is ( 250(A) + 500(B) ) or ( 500(A) + 250(B) ) = 750
Hence the option I selected was ( C )
But the OA says, ( E ).. Can you please let me know if I am missing something in my logic.
DS Question - machine and rate
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- gabriel
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.. this is where u went wrong ... bcoz it culd be ( 250(A) + 500(B)) or ( 250(A) + 125(B)) ... think about it ..tinni wrote:
.... Now from (1) and (2), if both the machines work simultaneously, then in we know the number of copies they produce in one minute which is ( 250(A) + 500(B) ) or ( 500(A) + 250(B) ) = 750 .....