Machine M processes a certain chemical product

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Machine M processes a certain chemical product at a constant rate. Does machine M process the product at a rate that is greater than 25 grams per second? (1 kilogram = 1,000 grams)

(1)Machine M processes the product at a rate that is greater than 92 kilograms per hour.
(2)Machine M processes the product at a rate that is less than 95 kilograms per hour.

OA:A

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by GMATGuruNY » Thu Aug 25, 2016 2:09 am
NandishSS wrote:Machine M processes a certain chemical product at a constant rate. Does machine M process the product at a rate that is greater than 25 grams per second? (1 kilogram = 1,000 grams)

(1)Machine M processes the product at a rate that is greater than 92 kilograms per hour.
(2)Machine M processes the product at a rate that is less than 95 kilograms per hour.
Since the two statements are in terms of KILOGRAMS PER HOUR, rephrase the question stem in terms of KILOGRAMS PER HOUR.

Determine the rate needed to process 25 grams in 1 second:
(25 grams)/(1 second) * (1 kilogram)/(1000 grams) * (3600 seconds)/(1 hour) = (25*3600)/1000 = 90 kilograms per hour.
Note that the units in color CANCEL OUT, leaving the resulting rate in terms of kilograms per hour.

Thus, for M to process more than 25 grams per second, the rate must be GREATER than 90 kilograms per hour.
Question rephrased:
Was the rate greater than 90 kilograms per hour?

Statement 1:
Since the rate is greater than 92 kilograms per hour, it must be greater than 90 kilograms per hour.
SUFFICIENT.

Statement 2:
If r=94, then the rate is greater than 90 kilograms per hour.
If r=89, then the rate is NOT greater than 90 kilograms per hour.
INSUFFICIENT.

The correct answer is A.
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