7th Grade · Statistics & Probability
Measure of Variability
7.SP.B.4
Definition
Describe how spread out data is. Range = max − min (uses 2 values). MAD = average distance from mean (uses all values). Both measure how much data varies.
Teach it
Where it is taught, with guided notes, practice, homework, an exit ticket and an interactive Teacher Deck.
Examples
- {4,6,7,8,9,10,12}: range = 12-4 = 8.
- Same data set: MAD = (4+2+1+0+1+2+4)÷7 = 2.
Key rule
Larger range or MAD means more spread out; smaller means more clustered.
Memory hook
Range is quick; MAD uses every point.