# statistics

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a quiz consists of 30 true or false questions. if the student guesses on each question, what is the standard deviation of the number of correct answers

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The Range Rule

The range rule tells us that the standard deviation of a sample is approximately equal to one fourth of the range of the data. In other words s = (Maximum – Minimum)/4. This is a very straightforward formula to use, and should only be used as a very rough estimate of the standard deviation.

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