Retailers that excel in neither convenience nor variety of merchandise tend not to be very successful. Yet many succ...

Daniel on September 11, 2018

Explanation

Why not D?

3 Replies

Max on September 14, 2018

@danieldepasquale we can diagram this as:

Premise: No Factors (NF) ==> not successful (S)
Contrapositive: S ==> not NF
Fact: there are some successful businesses with only one factor (OF)
C: Success does not imply both factors (BF), in other words, we CAN'T conclude: S ==> BF.

(D) says: No Factors (NF) ==> not good for baking (B)
So far, it seems parallel to the passage. But note what comes next:
B ==> One Factor (OF) the factor is "flavorful"
E ==> One Factor (OF) the factor is "flavorful"

So while in the passage we CAN'T conclude success necessitates BF, in (D) we are saying Baking necessitates at least one factor. Those are completely different conclusions, so they are not parallel even though they started off going in the same direction. I hope that helps!

Alexandra on December 28 at 01:57AM

This makes no sense

Ravi on December 28 at 07:13AM

@alymathieu,

What exactly makes no sense? I'll provide a general overview of the question here; if you have additional questions, be sure to let me know!

The stimulus states that retailers that excel in neither convenience nor variety of merchandise tend not to be very successful.

We can diagram this as

/EC + /EV - ->/S

Then, we learn that many successful retailers excel in just one of the areas and meet competitors' standards for the other. "Meeting competitors' standards" is just a complicated way of saying not excelling, so we know that there are cases where retailers excel in just one and are successful. This sentence can be diagramed as

EC + /EV - some - S and
EV + /EC - some - S

The stimulus then concludes that a retailer's success need not depend on excellence in both areas.

This can be diagrammed as

not (S - >EC and EV)

This is a valid argument. The full structure of the stimulus is

P: /EC + /EV - >/S
P: EC +/EV - some - S and
EV + /EC - some - S

C: not (S - >EC and EV)

The conclusion of the argument basically says that it's not the case that A is dependent upon B and C

not (A - >B and C)

The premises to support this are the ones that state that a retailer can excel in just one of the areas and still be successful

B + /C - some - A
C + /B - some - A

If you only need one of the areas to be successful, then it must follow that A is not dependent on both B and C

In looking at the answer choices, we are searching for the one that most closely parallels the structure we see in the stimulus.

Answer A says that runners who have only average speed and endurance are unlikely to win long-distance races

/Speed + /Endurance - >/Win

Then, it says that some long-distance champions, however, win by being above average in speed or endurance only. This sounds great so far, and it closely mirrors the stimulus.

Speed + /Endurance - some - Win
Endurance + /Speed - some - Win

Based on the conclusion we saw in the stimulus, we need to see a not (A - >B and C) structure in the conclusion of this answer in order for it to be correct.

The last part of answer A says, therefore, being above average in both speed and endurance is not necessary. This translates to

not (Win - >Speed and Endurance)

This exactly parallels the not (A - >B and C) structure we identified the conclusion of the stimulus as having. Additionally, the premises all match the structure of the premises in the stimulus, so this is our answer.

Answer choice D is tricky, as its conclusion exactly mirrors the not (A - >B and C) structure we're looking for. Answer D's conclusion is that apples that are best for eating need not be both firm and flavorful. This can be diagrammed as

not (Apples best for eating - ->Firm and Flavorful)

The conclusion matches. However, the premises do not match, and this is answer D's downfall and why it is incorrect.

D's premises are that apples that are neither especially firm not especially flavorful are unsuitable for baking.

/Firm + /Flavorful - >Unsuitable for baking

There is a shift in focus from "unsuitable for baking" in the premises to "best for eating" in the conclusion. This is not a shift that occurs in the stimulus.

If D were to have premises that match the stimulus, we would need to see something like there are apples that are firm but not flavorful as well as flavorful but not firm that are best for eating. This type of premise would match the stimulus. Due to this, we can eliminate D.

Does this make sense? Let us know if you have more questions!