# The Knewton Blog

Our monthly newsletter features edtech and product updates, with a healthy dose of fun Knerd news.

## SAT Prep Tip: The Case for Guessing

Posted in Test Prep on April 27, 2010 by

David Yourdon is a Content Developer for the Knewton SAT Course. He is also a cook and a saint.

High school sometimes feels like it hinges on two tests: the driving test and the SAT. And though you’re probably more excited to start driving than you are to start applying to college, there’s at least one respect in which the SAT is nicer than the driving test: It doesn’t penalize you for guessing!

“Now waaaaaaait a minute,” you say. “I know a thing or two about this SAT. If I guess on a question and get it wrong, I lose a quarter of a point. So how does it make sense to say there’s no penalty for guessing?”

Let’s work through it. For every multiple-choice question on the test, there are five answers choices. So if you take a random guess, you have a 1 in 5 chance of guessing correctly.

What if you guess on five questions in a row? Well, if you have a 1 in 5 chance of getting each question right, then odds are you’ll get lucky once in those five questions. For that one correct guess, the SAT will reward you with 1 point. For each of the four incorrect guesses, you’ll be docked a quarter-point, which means you’ll lose (1/4) + (1/4) + (1/4) + (1/4) = 1 point.

End result: You gain 1 point, and you lose 1 point, so you’re back to zero. No penalty!

Now imagine that you’re not guessing randomly. Maybe you’ve got a math problem that you can’t quite solve, but you know the answer has to be positive. If one of the answer choices is negative, your guessing odds go up. Or maybe you’ve got a sentence completion question, and you know the correct answer has to mean something like “angry.” If you’re sure that three of the words in the answer choices actually mean “friendly,” your odds go way up. Given that guessing randomly didn’t lose you any points, you can see how much you stand to benefit from guessing wisely!

Basically, if you can eliminate any answer choices, it’s in your interest to bubble something in. Educated guessing is rewarded on the SAT.

To be clear: this isn’t a trick. The test is designed with this aim in mind. A student who can eliminate lots of answer choices possesses more knowledge than a student who can’t eliminate any answer choices, and that knowledge deserves to be reflected in a higher score. If you never guess, you’ll never be rewarded for that knowledge.

Here’s another way to convince yourself: The SAT can’t tell colleges what you “really” know — it can only tell them what your score is. You may feel uncomfortable guessing on a question that you’re not 100% sure about.

You think you’ll be “caught.” However, the only thing that matters on the test is your final score. Since guessing tends to increase that score, be brave, and go for it!