Suppose we have set of blood pressure with a mean of 80 Diastolic, and a sample standard deviation of 10 points. If we assume a normal distribution of Diastolic blood pressures, between what two values can we be assured 99.7% of all Diastolic blood pressures will lie?
In order to help you with your answer, consider the following diagram of a normal distribution.
Moving 1 standard deviation away ...
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