If a certain sample of data has a mean of 31.0 and a standard deviation of 2.0, which of the following pairs contain two values that are each at least 2.5 standard deviations from the mean?
Choose one:  A) (27.0; 36.5)  B) (24.5; 38.0)  C) (28.0; 32.5)  D) (26.5; 35.0)  E) (29.0; 32.5)
The standard deviation is 2, so 2.5 standard deviations would be (2.5)(2) = 5.   The values between 26 and 36 are within 2.5 standard deviations from the mean.   The answer is (24.5; 38.0).
<result>B</result>
If a certain sample of data has a mean of 31.0 and a standard deviation of 2.0, which of the following pairs contain two values that are each at least 2.5 standard deviations from the mean?