How many hours will it take 6 identical machines, working at their con

Question

How many hours will it take 6 identical machines, working at their constant rates, to produce 1,200 components?

(1) Each machine produces 200 components.
(2) Two such machines, working at their constant rates, can produce 1,200 components in 9/2 hours.

NiharikaR · Answer

IMO B

St 2: 2/t=2/9
T=9hrs
6/9=1/t
t=1.5hrs
Since work ie 1200 components is same, I didn't consider 1200 anywhere

GMATinsight · Answer

Question : How many hours will it take 6 identical machines, working at their constant rates, to produce 1,200 components?

CONCEPT :  \frac{(Machine_Power * Time)}{Work} = Constant   
i.e.  \frac{(M_1 * T_1)}{W_1} = \frac{(M_2 * T_2)}{W_2}

i.e. We only need once scenario in which specific number of machines can finish work in specific time

Statement 1:  Each machine produces 200 components

Time and Rate are unknown hence 
NOT SUFFICIENT

Statement 2 : Two such machines, working at their constant rates, can produce 1,200 components in 9/2 hours

One scenario with rate and work is known hence the time of second case can be calculated as the work and Machines are already known
 /1200 = 6*T/1200

i.e. T = 3/2 Hours

SUFFICIENT

Answer: option B

Kinshook · Answer

Asked: How many hours will it take 6 identical machines, working at their constant rates, to produce 1,200 components?

(1) Each machine produces 200 components.
No time information is provided.
NOT SUFFICIENT

(2) Two such machines, working at their constant rates, can produce 1,200 components in 9/2 hours.
6 machines will take = 9/6 = 1.5 hours to produce 1200 components
SUFFICIENT

IMO B

CEdward · Answer

Why is it permissible to multiply 6 by Time/Work completed in statement 2? If you have 6 individuals, shouldn't the time taken to complete be faster? Why multiply the time? 
It seems to me as well that we are making an assumption that all the rates are equal? The statements don't say that though?

vatsal323 · Answer

But the question says "working at their constant rates". Which means their individual rates might be different. So based on the 2nd statement alone, we can't extrapolate the data to be true for all 6 machines

Statement 1 tells us that each machine helps build 200 components. Hence, all the machines have equal constant rates(there are 1200 components in total)

Hence, the answer should be C. Am I thinking correctly?

CrackverbalGMAT · Answer

Solution:

I- Each machine produces 200 components.

No information on the time is provided. Insufficient

II- Two such machines, working at their constant rates, can produce 1,200 components in 9/2 hours.

=>6 machines will take = 9/6 = 1.5 hours to produce 1200 components

(Sufficient)

option b

Devmitra Sen
GMAT SME

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How many hours will it take 6 identical machines, working at their con

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