ACT Preparation / Unit 15 ACT 1413 short lesson, about 20 seconds
Standard Deviation as Spread
Captions available
The idea
The standard deviation measures how far values typically lie from the mean. A larger standard deviation means more spread.
In practice
48, 50, 52 and 20, 50, 80 share a mean of 50, but the second set has the much larger standard deviation.
Where people slip
Compare spread by how far values sit from the center, not by how large the values are.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
- Nothing yet depends on this.
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