Mean, Median, Mode & Weighted Averages

Mode of a set (SAT)

This video explains how to identify the mode of a set of numbers. For easy problems, finding the mode is simple, but this video also covers the couple of curve balls that teachers (and the SAT) usually throw at you.

Median of a set (SAT)

This video focuses on the best process to find the median of a set while making the least mistakes possible, whether you're trying to find the median of a set with an even or odd number of members. Also covered is a particular type of logic question that shows up on the SAT, where they ask you "which of the following" you can do to a set without changing the median.

Calculating The Mean (Average) (SAT)

This video starts with how to find the average of a group of numbers, but then it gets into trickier word problems using the average formula. Also covered are SAT-style average word problems where they ask you to solve for a missing number based on the average of the rest of the group, or where you're supposed to say what the biggest member of a set could be based on the average of all the numbers.

Weighted Averages (a.k.a. figuring out your grade)

Whether you realize it or not, the weighted mean is used in every class you've ever been in: it's how your teacher calculates your grade based on how much each section of the class is worth (tests, homework, etc.)! So that's the main example we'll use in this video. And as an added bonus, we'll learn how to figure what grade you need on the final in order to get a certain grade for the semester.