You must know how to calculate the standard deviation from given summary data using the formula: \displaystyle \sqrt{\frac{\sum x^2}{n} - \bar{x}^2}

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## Glossary

### standard deviation

The square root of the variance; a measure of dispersion.

### union

The union of two sets A and B is the set containing all the elements of A and B.

**Full Glossary List**

More in this topic

1 Calculate standard deviation

2 Mean square deviation

3 Variance

4 Root mean square deviation

5 Standard deviation

6 Calculate rmsd 1

7 Calculate rmsd 2

8 Calculate standard deviation 2

9 Standard deviation on a GDC

10 Calculate rmsd 3

11 rmsd on a GDC

12 Calculate standard deviation 3

13 rmsd on a GDC 2

14 Standard deviation on a GDC 2

15 Variance

16 Standard deviation

17 Standard deviation 2

18 Standard deviation 3

19 Measures of deviation

20 Measures of deviation 2

21 Interquartile range

22 Interquartile range on a GDC

23 Skewness

24 Skewness O-test

25 Summary stats on a GDC

26 Timed O-test

27 Exam O-test 1

28 Exam O-test

29 Exam O-test 2

30 Exam timed O-test

31 Exam Question 2000

32 Exam Question 2000

33 Exam Question 2002

34 Exam Question 2002

35 Exam Question 2006

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37 Exam Question 2008

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48 Exam Question 2010

49 Exam Question 2011

50 Exam Question 2014