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Paper 1 · November 2021 · Confidence Intervals

120 bags of mealie-meal have mean mass 750g and standard deviation 3.9g. What is the standard error of the mean, correct to 3 decimal places?

Model answer

0.356

Also accepted: 0.3560

Explanation

The standard error of the mean is

s/\sqrt{n} = 3.9/\sqrt{120} = 3.9/10.954 = 0.356

g.

Derived from ZIMSEC Statistics Paper 1, November 2021, Q1

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