The question asks us to identify the gap between the premises and the conclusion.
S-shaped rake reduces the pull stroke compression stress to 1/5 of a straight handled rake. But its push stroke stress is 5x of the straight handled rake. Neither the push nor the pull stroke with a straight handled rake causes injury, but compression stress during the push stroke with the new rake is above the danger level. Therefore, straight-handled rakes are better for minimizing spinal injury.
The conclusion requires us to assume that compression injuries are the only source of injuries resulting from raking. If there are other sources of injuries that we have no information on, we cannot conclude that straight-handled rakes are definitely better at minimizing injury, we could only conclude that straight-handled rakes are better for minimizing compression stress injuries.
(E) is irrelevant because the conclusion specifically compares straight-handled and S-handled rakes - "straight-handled rakes are better than the new [S-handled] rakes." (E) could be correct if the conclusion said "Straight-handled rakes are better than [any other rake design]"
Does this make sense?
Let me know if you have any further questions.
PaytonjdApril 22, 2023
@Irina Is this supposed to be a strengthen with necessary premise question instead of a strengthen with sufficient premise question? This is in my Sufficient Premise practice questions, but your explanation talks about what the conclusion "requires" us to assume, which sounds like a Necessary Premise question.
I don't see how the correct answer choice -- "Compression stress resulting from pushing is the only cause of injuries to the spine that occur as a result of raking" -- is sufficient to guarantee the conclusion, that "straight-handled rakes are better than the new rakes for minimizing risk of spinal injury". If it's a super premise, shouldn't it be able to guaranty the conclusion without the support of any other premises? It seems like, in order to get to this conclusion, you have to the use other premises in the passage, in addition to the premise provided in the correct answer choice.
Emil-KunkinApril 25, 2023
Hi, this is a sufficient assumption,option question. It is asking us which answer choice would fix the argument, not which answer choice the argument depends on. However the right answer I think is both a sufficient assumption and a necessary assumption.
I don't know what you mean by super premise, but the right answer for a sufficient assumption question doesn't need to guarantee the conclusion without any other premises. It needs to fix the argument, which of course will usually involve the other stated premises.
