Answer: 15.
- A 15
- B 12
- C 20
- D 8
Correct answer: A. 15
Explanation: Range = largest − smallest = 20 − 5 = 15.
In a perfectly normal (bell-shaped) distribution, mean, median, and mode all coincide at the centre; about 68% of data falls within 1 standard deviation of the mean, 95% within 2, and 99.7% within 3 - the empirical rule used to judge how typical or extreme a value is.
Concept context
Mean, median, mode, standard deviation, and data interpretation