A normal distribution of data has a mean of 15 and a standard deviation of 4 How many standard deviations from the mean is 25 ?

Subtract the mean from the value: 25 − 15 = 10. Divide that difference by the standard deviation, 4: 10 ÷ 4 = 2.5. So 25 is 2.5 standard deviations above the mean, which is choice C, “2 point 5.”

AI-written and checked against the verified answer.