This is a resolve, reconcile, explain question, as the stem states: Which one of the following, if true, most helps to explain why the new silencing device will make lower electricity consumptions possible?
As mentioned in our question stem, this stimulus is about a new silencing device. This device negates the sound waves produced by domestic appliances. Sounds high-tech! Next we learn that this device differs from conventional silencers by actively eliminating noise, and because of this vacuum cleaners which incorporate the device will consume less electricity. Interesting, but I’m not sure I see the connection; why does less noise mean less electricity? The correct answer is going to fill this gap, and give us a reason for why this new silencing device’s noise cancelation will save power. Let’s see our options:
Correct Answer Choice (A) Makes sense! With the new device, the designers can just focus on making the motor as efficient as possible because the noise problem is solved by the device, so the vacuum will consume less electricity.
Answer Choice (B) If anything this suggests the device would increase electricity consumption.
Answer Choice (C) This is just a random fact, and clearly irrelevant to what we are trying to explain.
Answer Choice (D) But we are told the new device will operate with lower electricity consumption. This answer only says that the device allows more electricity consumption, which does nothing to explain why it is has actually decreased.
Answer Choice (E) But how would making them heavier and less mobile lead to lower electricity consumption? This doesn’t give us a satisfying explanation like A does.
This is a must be true question, as the question stem demands: If the statements above are all true, which one of the following must also be true*?*
The first sentence tells us that Angela will earn her Psychology degree once she completes two courses; one in experimental design, the other in developmental psychology. Unfortunately for Angela, experimental design is a pre-requisite of developmental psychology, and won’t be available till the following term, so Angela won’t finish her degree for at least two more terms. The first sentence tells us that the two courses are enough (i.e. sufficient) for Angela to get her degree. We should infer from the second sentence that they are also required (i.e. necessary) for Angela to get her degree, and that ED is required for DP. It’s important for us to recognize that Angela getting a psychology degree and Angela completing developmental psychology are both sufficient and necessary for each other, and that what we have is therefore a biconditional relationship between the two events. If we were to translate these requirements into a conditional chain, it would be something like: P Degree ←→ DP → ED. Since this is all the information the stimulus has for us, we should expect the correct answer to be something guaranteed by these combined conditionals. Let’s see what the answer choices have in store for us:
Answer Choice (A) We’ve been told nothing about how long the course will take.
Answer Choice (B) We’ve been told nothing about the relative difficulty of the two courses.
Answer Choice (C) We’ve been told nothing about the pre-requisites for experimental design, just that it is required for Angela’s degree and to take developmental psychology.
Answer Choice (D) We’ve been told about the requirements for Angela to get a degree, but we can’t infer that is true of anyone seeking a psychology degree in her university. Maybe there are several options to receive the degree, but Angela’s course selection has committed her to needing these two credits specifically.
Correct Answer Choice (E) Angela’s degree needs both DP and ED, but since DP already requires that she have completed ED, then she must have satisfied all the requirements for her degree if she completes DP.
This is a sufficient assumption question, as the question stem asks: Which one of the following is an assumption that would permit the conclusion above to be properly drawn?
We’re told that every photo must in some ways be true - that stuff in between the commas is science stuff that basically means that because the light of what we capture hits the film. The next sentence begins with a “but” which indicates a potential pivot; the argument goes on to say because of things like Photoshop or angles/posing (cue social media) it doesn’t show the whole trust and is false. Our conclusion comes in and says nothing can ever be proven with photos. First, “nothing” is very strong. Second, being false and proving something are two different, albeit related, ideas. What if you can prove something to be false with an altered photograph by comparing it to what’s actually the case? Let’s link these ideas up with a rule: “If a photograph can be altered to prevent showing the whole truth and is therefore false, then nothing can be proven with it.”
Correct Answer Choice (A) This is correct because it links up our premises with the conclusion and forced our conclusion to be true. While it’s not a perfect paraphrase of our rule, it conveys the same thing.
Answer Choice (B) We’re told that photographs cannot express the whole truth. What does knowing the whole truth have to do with our argument? With our premises and this answer, we cannot force the conclusion.
Answer Choice (C) Being able to figure out whether or not a photograph is truthful does not help push out our conclusion; we still won’t know what is true or false, and this answer choice does not bridge the gap between something being false and figuring out what is not provable.
Answer Choice (D) This does not help justify that nothing can be proven with a photograph. The answer choice adds more information about finding out the truth of the scene of the photograph and then determining what we can use to photograph as evidence. This is more information unrelated to justifying our conclusion.
Answer Choice (E) This would weaken our argument - this is out.
This is a sufficient assumption question because the question stem says: “conclusion follows logically…if which one… is assumed?”
Sufficient assumption questions tend to be very formal. We’re looking for a rule that would 100% validate the conclusion, specifically by bridging the premise and conclusion through the rule. Not only are we extrapolating the rule from our argument, but we’re also using that rule to render the argument “valid.” The way to prephrase our answer choice is by tying our premises and conclusion together into a rule: “If [premise] → then [conclusion].”
Our first sentence is very straightforward: in bureaucracies, decisions involve many people. The sentence just elaborates on this by saying that no one person have more authority than the next person. These are both our premises.
Our conclusion states that in bureaucracies, risky projects are never undertaken. That’s a big jump! From “bureaucracy decisions involving multiple people” to concluding “risky projects are never undertaken”? What if that is the exact they take on risky projects? For example, they could say that because many people are involved, they’re able to prepare for every outcome.
In order for our conclusion to follow, we need to link up the idea in the premises to the conclusion: when multiple people are involved in decisions and no one has the authority, risky projects will not be taken.
Answer Choice (A) This isn’t correct. We’re trying to make our conclusion about risky projects not being taken on valid; the fact that projects always require risk doesn’t help the gap in our argument.
Answer Choice (B) This isn’t correct either. The gap here is that the argument assumes that have many people involved in a decision means that no risky project will be taken. If we plug this into our stimulus, this doesn’t help validate our conclusion. It could support it, but there are too many assumption we need to make to arrive to our conclusion.
Answer Choice (C) This is more or less what our premises are trying to say, but again, it’s not helping to validate our conclusion about risky project not being taken on in bureaucracies. Additionally, we’re not concerned with what groups of people will take risks - we specifically interested in bureaucracies who will not take risks.
Correct Answer Choice (D) We said we weren’t interested in people who take risks, but this is a conditional statement! The answer choice is saying “when risk take, then single individual power to decide.” Taking the contrapositive of this would be: if multiple people have the power to decide, the risk is not taken. See how “no risk taken” is in the necessary condition? This is the NC in our rule, and it’s also our conclusion. Our premises trigger the contrapositive of this answer and allow us to draw our conclusion.
Answer Choice (E) This isn’t correct; what people do on there own is outside the scope of their decision as a group. This doesn’t help us draw our conclusion.