Sufficient Assumption | LSAT Logical Reasoning

Sufficient Assumption questions in Logical Reasoning are all about finding the missing link in the argument. Learn how to use conditional logic to find the gap in the argument's reasoning.

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[kamacazi]

Oh my God this video is heaven sent. I was having major problems trying to figure out how to answer sufficient assumption questions and I followed LSAT Lab strategy and I got all correct and boosted my score from 15/23 to 20/23 cause it was an area of weakness for me.
Please follow their strategy it does put the question into a visual perspective.

A——B——C——D

A and B are usually two sets of evidence given in the question; the evidence can be a conditional relationship or just stated facts that you have to link together, D is always the conclusion. You have to find C or the link between B- D which is the sufficient assumption. If you map the question like this I guarantee you’d figure out what the assumption is. It is usually a mix between the B and D. You have to find a common ground that would link the conclusion to the premise B and that usually gives you C or the sufficient assumption.

Thanks LSAT Lab.

[randomvideos_]

So helpful, finally someone I understand easily when explaining. Thank you!

[ariannaramirez]

THIS IS SO HELPFUL!!! I got the example problems right. I also really appreciate how you clearly explain why the wrong ones are incorrect

[lraoux]

Make sure not to look for an assumption that is already being made in the stimulus, but rather an assumption that, if made, needs to guarantee the conclusion. In other words, don’t mistake these for necessary assumption questions.

[ts]

The part where you ponder on how all of the aluminum of group L possibly may have not made it over to Group M using the mixing bowl mindset is where I struggle the most. My mind has the hardest time coming up with these "what if" scenarios that would disprove the conclusion. Ive got to learn how to think this way.

[lraoux]

I fell for the Negation choice (Answer D) about Murray on the executive board/Admin question; thought B was out of scope. One important takeaway from this lesson is that SA questions can be tricky because of irrelevant relations (I noticed this in another SA question). Murray, who is in the conclusion of the stimulus, is actually irrelevant in finding the right answer choice. Another key takeaway is that answers that seem too strong make for good choices, and are often better than assumptions weaker in degree. In contrast, for inference/strongly support question types, strong answer choices generally should be eliminated, as they are harder to prove, so it’s important to know the question type.

[christinea]

I don't understand why this isn't clicking :'(

[nicolewinn]

I wish I could shake your hand, or give u a hug. Thank you so much..

[Stunninjavi]

Is possible to have an answer choice be both necessary and sufficient? Or is it also possible that one answer choice can be necessary but not sufficient for the same given argument? If so, can you provide an example? Thank you! And by the way, great content!

[randomvideos_]

Do you do personal tutoring sessions? If so, I am interested.

[jinsdancelog]

Do we solve Necessary Assumptions that require linking the same way we do Sufficient Assumption questions? I'm stumped on finding a difference between the two if there are any. I'd really appreciate some help with differentiating the two because I feel like I'm answering a necessary assumption question the same way I would a sufficient assumption and I don't know if that's the correct way to do it.

[abandonallhope.]

For the last question, is answer choice C both a necessary and sufficient assumption? Because if it is NOT true that all of the aluminum is recovered when cans are recycled, wouldn't that destroy the argument's conclusion?

[celiamyers]

In question 6, how come the missing link isn't about the felony conviction? I'm not sure I understand the negation of answer choice (D).

[WaisNoah]

Hi, this was very very helpful! Do you have any videos on complex questions that require long conditional chains?

[martinic]

is there a faster way to analyze these types of questions and find the answer because come LSAT exam you have 35 minutes for the whole section so there isn't that much time to go through all of this

[riyakapoor]

Thankyou please make more for lsat india!!

[nuaxmk]

If a question stem says, .."which one of the following, if true, most seriously calls into question.." would it be a sufficient assumption question?

[riyakapoor]

Lsat india is on 14June please post more

[anirbanmukherjee]

2007, S2, Q6: answer choice A is not a negation. Question stem gives us executive board —> undergraduate + no felony. This is because felony —> no board, so the contrapositive combined with the first condition gives us that. Option A specialises this condition to board —> masters + no felony. This is because eligibility conditions are necessary conditions. Ie it’s not no felony —> board as shown in the visual but rather board —> no felony. Eligibility does not imply board membership. It simply means this condition must be present for the board members. Of course it could also be that there are multiple alternative eligibility criteria in which case it is not even a necessary condition but regardless it’s not a sufficient condition, and so not a negation.

[jorgetorresbenitez]

I dislike this question types more than any question in the LSAT. Even worse than parallel flaw.