The only way that bookstores can profitably sell books at below-market prices is to get the books at a discount from ...

Victoria May 13, 2019

Hello,

I'm a bit confused as to what you mean by "these type of questions" being "opposites."

In this case, the reason that B is the correct answer choice is because "the only" precedes a sufficient condition (as opposed to "only" which precedes a necessary condition).

Therefore, the sufficient condition is bookstores profitably selling books at below-market prices (PSB below MP) and the necessary condition is getting a discount from publishers (D) which results in the mapping:

PSB below MP - > D

Hope this was helpful! Please let us know if you have any further questions or need more clarification.

AndrewM August 2, 2020

What would have been the correct answer if it said "only" instead of "the only"? I think I picked the choice that is designed for the "only" choice instead of "the only"

shunhe August 4, 2020

Hi @AndrewM,

Thanks for the question! If the stimulus had said “only” instead of “the only,” the correct answer choice would’ve been (C) or (A). “The only” will introduce the sufficient, whereas “only” will introduce the necessary. So if the stimulus had read something like

“Only bookstores that can profitably sell books at below-market prices get the books at a discount from publishers.”

Or

“Only if bookstores profitably sell books at below-market prices can they get the books at a discount from publishers.”

Then the correct diagram would’ve been

Get books at discount from publishers —> Bookstores profitably sell books at below-market prices

And that’s what (C) says. It’s also what (A) says, since (A) is just the contrapositive of that statement, and so they’re logically equivalent. So either of those would’ve been acceptable as an answer choice if it were “only” instead of “the only.”

Hope this helps! Feel free to ask any other questions that you might have.