A sample of 100 patients has a standard deviation of 20 for a measurement. What is the standard error of the mean?
Answer and explanation
Correct answer: D. 2
- Step 1: The standard error of the mean is the standard deviation divided by the square root of n. Step 2. The square root of 100 is 10, so SE = 20/10 = 2. Answer: 2. Why not the others: 20 is the standard deviation itself. 0.2 would result from dividing by 100. 200 results from multiplying by 10.
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