Question of the Day! PrepTest 55, S.1, Q.15

A lot of people studying for the LSAT have troubles with inference questions. One question that was giving some of my students trouble is from Prep Test 55, Section 1, Question 15.

This question is about Zach’s Coffee Shop. (I cannot legally post the question unless I give licensing fees to LSAC). However, I am going to explain why each answer choice is wrong or right.

Analysis of the Question:  Zach’s coffeeshop has poetry readings almost every Wednesday. And then the question tells us that Every day that holds a poetry reading has 1/2 priced coffee.

We are looking for an inference – which is a statement that must be true based on a sentence or combination of sentences.

Therefore, something that MUST be true based on the stimulus is that – on the Wednesday’s with a poetry reading, the coffeeshop must offer 1/2 priced coffee. Let’s take a look at the answer choices to see if something matches our prediction.

Answer Choices:

(A) The stimulus does not tell us that Wednesday is the most common day to offer 1/2 priced coffee, since the stimulus does not tell us that they ONLY offer 1/2 priced coffee when there are free poetry readings. For all we know the coffeeshop offers 1/2 priced coffee everyday.

(B) Like A, the stimulus does not tell us that the coffeeshop only has poetry readings on Wednesday’s. Perhaps they have free poetry readings every single Friday.

(C) We know that: if there is a free poetry reading —> then there is 1/2 priced coffee. But, we cannot assume the reverse. We don’t know that every time there is 1/2 priced coffee there is also a free poetry reading. Be careful not to mix up necessary and sufficient conditions!

(D) CORRECT – We know that: Almost every Wednesday –> free poetry reading —> 1/2 priced coffee! Which is what this question is saying. If you were confused by the “most, if not all” part of the question, just note that — they could still offer 1/2 priced coffee on the Wednesday’s without poetry readings. They don’t have to have 1/2 priced coffee on those days, but they could offer it. That is why it is possible that they could offer 1/2 priced coffee on all Wednesdays. (“Almost every” means 51-99%, but since the 1% of days could still have 1/2 priced coffee for all we know – this answer choice is correct)

(E) Since we now understand why the coffeeshop could offer 1/2 priced coffee every Wednesday. This answer choice must be false, since we do not need to have a day without 1/2 priced coffee. (and “some” means – at least one)

If you have any questions about this feel free to send me a message or post in the comments below!