Feb. 7, 2021

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Here's the coolest thing about improving your ability to answer statistics questions on the ACT: When we say that it'll improve the odds of you getting a high score, you'll know exactly what that means! Here how to break down two major types of probability questions.

Also keep an eye out for questions that ask for the probability of something NOT happening. To calculate this, simply take 1 minus the probability of it happening. From the example above, we already determined there's a 2/5 or 40 percent chance that you or your BFF will be the commencement speaker. Therefore, our equation to determine the probability of neither of you being selected as speaker is 1-2/5, which equals 3/5, or 60 percent.

One way that the ACT likes to make finding the odds more complicated is by asking you to do it more than once in a single problem. When looking for the expected value, you'll have to find the odds of several individual events, determine what each one is worth, and then add the results.

**EXAMPLE: I**f a basketball player has a 60 percent chance of making a 2-point shot and a 30 percent chance of making a 3-point shot, what is the expected value from a player who makes two 2-point attempts and two 3-point attempts?

The "events" in this case are the number of 2- and 3-point attempts.

2, 2, 3, 3

In this case, you've been given the odds, which is the percentage chance of a thing happening.

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Now that you have the correct number of events and their probabilities, it's time to solve.

= 1.2 + 1.2 + 0.9 + 0.9 = 4.2

**ANSWER: **The expected value for this scenario is 4.2.

Keep studying these terms and questions until you can quickly determine what to look for. Doing so is how the savviest students get what they *want *out of the *total* score of 36.

If you need more help studying up on ACT Math, check out our prep book for the exam. Plus, you can subscribe to our YouTube channel for more content to help you succeed in all your college admissions goals.

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