#22 - On Wednesdays, Kate usually buys some guava juice

[lkr123]

Can someone please explain why A is correct instead of B?

Thank you!

[Luke Haqq]

Hi lkr123,

To see why (A) rather than (B) is correct, consider how the stimulus would be diagrammed:

• Weds guava juice local health food store

The "Weds guava juice" comes from the language, "On Wednesdays, Kate usually buys..."


Answer (A) matches the original structure:

• Dinners at Cafe Delice use main kitchen teach at culinary institute

Answer (B) is close, but it misses the " "--

• Dinner at Cade Delice use main kitchen teach at culinary institute

[rabedelahad]

I'm confused why it is not D, could someone please explain it?

[Daniel Stern]

The problem with answer choice D is that the teachers are merely allowed to use the kitchen, whereas in credited response A the teachers were the only people who could use the kitchen.

It's the exclusivity of the teachers use of the kitchen in A that allows us to conclude that dinners prepared in the kitchen must be prepared by the teachers.

In D, dinners prepared in the kitchen might be prepared by the teachers, most of whom are allowed to use the kitchen, but the dinners might also be prepared by someone else who is allowed to use the kitchen. D doesn't rule that out. Maybe the culinary insitute allows most teachers to use the kitchen, and most of the janitors, too. And it's those janitors who cook the Cafe meals!

Good luck in your studies,
Dan

[isoifer]

Can you please explain why E is incorrect? I notice some subtle differences between A and E and want to make sure I understand correctly why A is preferred.

[Alex Bodaken]

isoifer,

Thanks for the question! The problem with answer choice (E) is that it is not valid reasoning, while the stimulus is. Answer choice (E) says: "Only teachers at the Culinary Institute are allowed to use the main kitchen of the institute. Dinners at Cafe Delice are usually prepared by Culinary Institute teachers. So dinners at Cafe Delice must sometimes be prepared in the main kitchen of the Culinary Institute." But this conclusion doesn't follow. I could represent the premises thusly:

Use main kitchen teachers at culinary institute
Dinner at Cafe D prepared by culinary institute teachers

This doesn't really tell us much of anything. It means that dinners prepared in the main kitchen are from culinary institute teachers, but it doesn't tell us that is the only place they can prepare them...and so the conclusion "dinners at Cafe Delice must sometimes be prepared in the main kitchen of the Culinary Institute" isn't true...it could be that they are prepared by culinary institute teachers somewhere else. Because the reasoning for (E) is invalid, while the reasoning for (A) is valid, (E) cannot be the credited answer.

Hope that helps!
Alex

[LSAT2018]

Wednesdays (Most) → Guava Juice → Local Health Food Store
Wednesdays (Some) → Local Health Food Store

Dinners (Most) → Main Kitchen → Teachers at the Culinary Institute
Dinners (Some) → Teachers at the Culinary Institute

Would answer (A) still be acceptable had it said most dinners at Cafe Delice must be prepared by Culinary Institute teachers?

[Adam Tyson]

With that change, answer A would still necessarily be true, but it would no longer be parallel to the stimulus, because of the shift from a "some" premise to a "most" premise. The test authors would not be likely to present such an answer choice as the best answer since it is not truly parallel.

[theamazingrace]

Hi, I found this question to be difficult because they kinda all look the same at first. What is the best way to approach questions like this I always find them hard and time-consuming? One thing I do know is that it is important to match the tone of the conclusion and premise(s). The stimulus here has 1 most, 1 all and 1 sometimes. A is the only answer choice that says in its conclusion that " at least some" is that a good way to quickly eliminate the other answers?

Thanks!

[Adam Tyson]

That approach won't work here, theamazingrace, because answers A, C, D, and E ALL have conclusions about "some," even if they don't use the exact words from the stimulus (two are "at least some" and two are "sometimes", and those mean the same thing). Instead, the best approach is to diagram the stimulus with a combination of Formal Logic and Conditional Reasoning and then match the answer choices to that diagram. To see how, look over Luke's post earlier in this thread!