Weight Loss Made a Bit Easier: Realistic and Practical Advice for Healthy Eating and Exercise
Available on Amazon.com in paperback/Kindle formats for $6.25/$2.99. Please click here for details.
Home | My Math and Education Books | Math Lessons | Ask a Math Question
Site Info | Contact Info | Tutoring Info | LarryZafran.com | Tweet
Lesson 52: Introducing the Mean (Average)
The mean is a topic that comes up again and again in math and in everyday life. It's important that you understand it fully. This lesson introduces you to the basics.
The word mean is just a fancy word for average. You hear about averages all the time, especially when it comes to test scores. If you scored 80 and 100 on two tests, you probably know that your average is 90, but you might not be sure exactly why.
To find the average of a list of numbers, just add them up, and then divide the sum by the number of items in the list. Memorize this procedure.
For example. Let's say you have test scores of 72, 81, 89, 93, and 100. Add them up to get 435. Divide by the number of scores, 5, to get 87, which is the average (mean).
Sometimes your answer will have a decimal component. In cases like that, you will be told to what place you need to round your answer. Sometimes you want your answer to the nearest tenth, such as 92.7. In the case of test scores, it would probably be fine to just round your answer to the ones place. For example, 87.6 would just become 88.
Remember that you can
ask a math question if you have additional
questions about a topic, or you can
contact me if you have any comments
or suggestions for this site.