If the variance of test scores in a class test is 36, what is the standard deviation?
Answer and explanation
Correct answer: A. 6 marks
- Step 1: Standard deviation is the square root of the variance. Step 2. Square root of 36 is 6. Answer: 6 marks. Why not the others: 18 marks divides by 2; 72 marks doubles the variance; 1296 marks squares the variance.
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