Mean absolute deviation measures how far each value sits from the mean. To do it you find a mean (add ÷ count), then subtract to get each distance, then average those distances. So subtraction, addition, and division all need to be warm.
Answer these 3, then press Show my path. No grade — this just points you to the right level.
1. What is 9 − 5?
2. How far apart are 7 and 10 on a number line?
3. What is 8 ÷ 4?
A deviation is how far a value is from the mean. Distance is always a positive number — you take the bigger minus the smaller. Then you average all the distances.
Your quick check picks one for you, but you can switch any time:
Level 0 Just find the distance — bigger minus smaller.
A. How far is 6 from 4? (6 − 4)
6 − 4 = 2.
B. How far is 3 from 5? (Take bigger minus smaller: 5 − 3)
Distance is always positive: 5 − 3 = 2.
C. Add the distances: 2 + 2 = ___
2 + 2 = 4.
Level 1 Find distances from a mean, then add them.
A. The mean is 5. How far is the value 9 from the mean?
9 − 5 = 4.
B. The mean is 5. How far is the value 2 from the mean?
5 − 2 = 3 (bigger minus smaller).
C. Add those distances: 4 + 3 = ___
4 + 3 = 7.
Level 2 Average the distances (a mini-MAD).
A. The distances from the mean are 2, 4, 6. What is their total?
2 + 4 = 6, + 6 = 12.
B. There are 3 distances totaling 12. What is the average distance (12 ÷ 3)?
12 ÷ 3 = 4 — that would be the MAD.
1. The mean is 6. How far is the value 10 from the mean?
10 − 6 = 4.
2. The distances are 1, 3, 2. Add them, then divide by 3 for the average distance.
1 + 3 + 2 = 6, and 6 ÷ 3 = 2.
You've practiced exactly what Lesson 8-3 uses. Time to dive in.
Start Lesson 8-3 →