Answer: 100.
- A 4
- B 25
- C 100
- D 20
Correct answer: C. 100
Explanation: Sum = mean × number of values = 20 × 5 = 100.
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