Inference Questions: Wrong Answer Types

There are several different kinds of “inference questions” on the LSAT. Some are perfect examples of pure conditional reasoning, such as the “must be true” and “must be false” questions in logical reasoning and logic games. Others are “softer” inferences, such as the “most strongly supported” –questions in logical reasoning and the “author is most likely to agree” type statements in reading comprehension. There are important similarities between these different questions, and even more important similarities between the wrong answers to these questions.

In this post, we will look reading comprehension inference questions. These are functionally identical to the “most strongly supported” logical reasoning questions, with the added challenge of searching sixty lines of reading comp to find the answer instead of the typical six-to-twelve line logical reasoning stimulus. All that text means that a clever and imaginative student can conjure up some reason a wrong answer might be right. (I’ve seen it done… and I’ve even done it myself!) That is a problem for LSAT takers and for the people who write it. The LSAT authors always include the word “most” in phrases like “which of the following is most strongly supported” to respond to students who call up to complain that some other answer is arguably correct, but they don’t want to have that conversation. They want each wrong answer to be provably wrong–and there are only so many ways to do that. Learn that handful of “wrong answer techniques,” and you will get faster and better at inference questions.

Quantities and Comparisons

The easiest wrong answer involves a “quantity” claim that is not supported by the text. The easiest way to generate such an answer is to take a sentence that is clearly stated in the text and then add one “quantity word” that isn’t in the text. Thus, if the passage says “ultraviolet light causes skin cancer” don’t be surprised if you see a wrong answer that claims that “ultraviolet light is the primary cause of skin cancer.”

“Comparison words” are common in wrong answers, for several reasons. Consider an answer like “The diversity of plant species was greater in ancient forests than in modern forest.” For that to be the right answer, we will need information about the plant diversity in ancient forests, the plant diversity in modern forests, and some common unit of measurement that allows us to compare them. It isn’t enough to say “there were lots of plant species in ancient forests” and “modern forests have many different species.” That doesn’t tell us which has more. Comparison answers can be right, but only if there is clear and specific information to support it–and that is the exception, not the rule.

Sounds good but not supported

An answer is provably wrong if it includes an element that never appears in the passage. The LSAT authors must tempt test-takers to choose such an answer, so they often write an answer choice that appeals to the readers common sense or preconceptions. If your initial response to answer is “that is probably true,” be careful! The question before you is not “what is true” but “what is supported by the text.”

Reading Comprehension and Reading Speed

If you are a very slow reader, please skip to bottom of this post now. (If you are a very fast reader, on the other hand, you can skip the last section.)

Reading Speed

The LSAT is a “speeded” test, which means that the majority of test takers are not able to complete it. On three of the four scored sections, your time is mostly spent on choosing your answers, but in the Reading Comprehension section, a significant chunk of time is spent just reading the  passage. Then you spend a lot more time re-reading the passage to try to decide on the answer.

The worst mistake a slow reader can make is to skim through the passage and the questions and circle answers that “sound right.” My students who have tried this approach on PrepTests consistently get worse results than if they just had flipped a coin. There’s a reason for this–the folks who write LSAT tests spend a great deal of time and energy trying to come up with wrong answers that sound right. Remember: their job description is to write tests that make smart people feel stupid.

If your LSAT goal is something under 165, reading speed is important but not critical. You can flip through the four passages, decide which one you like least, and skip it. (Don’t forget to bubble in a string of answers, however. On average, you’ll get one in five right.) That gives you eleven minutes and forty seconds per remaining passage.  If you really comprehend what you have time to read, and get familiar with reading comprehension questions, you could skip an entire passage and still get 20 out of 25 questions right. If you got every other question on the LSAT right, you’d be at the 99th percentile. If your goal is 165, you’re in good shape.

Most of us can’t count on getting every other question right and lucking out on a couple of random answers on the passage we skipped. So if you are a relatively slow reader who wants to go to a top five law school, you’re going to need to do something more.

One solution would be to change your goals. Top five law schools are full of top five students with top five reading speeds. Getting accepted to the law school of your dreams might turn out to be a nightmare if you find you can never keep up with the load.

Another solution would be to change your reading speed. You don’t need to be a speed reader to do well on the LSAT, but you can’t afford some of the bad habits that make some readers extra slow. The challenge of the LSAT may be just the motivation you need to overcome some problems that have plagued you since grade school.

Advice for Slow Readers

  1. Measure your reading speed (speed test courtesy of
  2. Try to identify why you read slowly (Note: the site I am sending you to has a short and simple list of reading problems. It is also trying to sell you a speed reading course. I have no reason to think their reading course is worth your money!)
  3. Try Method 1 and/or Method 2 of these 3 Ways to Read Faster. (Do not try Method 3 on the LSAT!)
  4. Measure your reading speed again after a week or two of regular practice. If your speed is increasing, keep practicing! If you don’t see any improvement, do more research on your own or contact a reading tutor.