P1: Certain Set of Instruments were made from Nylon and Steel
P2: 10 * En = 3.4 * (Em)
50 * Es = 2.1 * (Em)
Where,
En = Energy Required Sterilization of Nylon
Es = Energy Required Sterilization of Steel
Em = Energy required for Manufacturing set of instruments
(A) The 50 complete sterilizations of nylon instruments used more energy than did the 50 complete sterilizations of the stainless steel instruments.
5* (10 * En) = 5*3.4* Em = 17 Em (since Em is always positive)
50 Es = 2.1 Em < 17 Em So We can conclude (A) from above Premises. ( So This is not the Answer)
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(B) More energy was required for each complete sterilization of the nylon instruments than was required to manufacture the nylon instruments.
We do not know anyting about the values of En and Em So we cannot compare these two values. So this could be the answer
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(C) More nylon instruments than stainless steel instruments were sterilized in the study.
This is a out scope choice. Nowhere in the Premises, the author talked about the number of nylon / steel instruments. So leave it.
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(D) More energy was used to produce the stainless steel instruments than was used to produce the nylon instruments.
This is also an out of scope answer choice.
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(E) The total cost of 50 complete sterilizations of the stainless steel instruments was greater than the cost of manufacturing the stainless steel instruments.
This is also an out of scope answer choice.
Author did not talk about the price at all.
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So the answer is : Choice B.