SAT Math formula sheet · all 24 · Problem-Solving and Data Analysis · #16 of 24

Standard deviation on the SAT: How It Is Tested

One-variable data: distributions and measures of center and spread

Standard Deviation diagram for the SAT: For standard deviation, simply think of spread. Just remember that one word. In the examples above, B has more spread th
What it is really testingFor standard deviation, simply think of spread. Just remember that one word. In the examples above, B has more spread than A, so B has the larger standard deviation. C and D always go up by 1, so their spreads are the same.

The question from the sheet

Medium
SAT Problem-Solving and Data Analysisanswer D
Which of the following lists represents a data set with the largest standard deviation?
A70,70,70,70,7070, 70, 70, 70, 70
B68,69,70,71,7268, 69, 70, 71, 72
C62,66,70,74,7862, 66, 70, 74, 78
✓40,55,70,85,10040, 55, 70, 85, 100

How the diagram applies

  1. Standard deviation is spread from the mean, and every list here has mean 7070.
  2. List A has no spread at all. B steps by 11, C by 44, D by 1515.
  3. The most spread out list has the largest standard deviation: D.

Answer: D

That is 1 of 24.

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Common Questions

It comes up as an SAT one-variable data: distributions and measures of center and spread question. For standard deviation, simply think of spread. Just remember that one word. In the examples above, B has more spread than A, so B has the larger standard deviation. C and D always go up by 1, so their spreads are the same.

Standard deviation is spread from the mean, and every list here has mean 70. List A has no spread at all. B steps by 1, C by 4, D by 15. The most spread out list has the largest standard deviation: D.

No. The SAT reference sheet is twelve geometry formulas and three notes, and Standard Deviation is not one of them. It is one of the 24 things the test expects you to know without being given them. See what the reference sheet does cover at /blog/sat-math-reference-sheet.