Question 48
Measures of Central TendencyThe arithmetic mean of the ages of 30 pupils in a class is 15.3 years. One boy leaves the class and one girl is enrolled, and the new average age of 30 pupils in the class becomes 15.2 years. How much older is the boy than the girl?
- A.30 years
- B.6 years
- C.9 years
- D.3 years
- E.1 year.
Show the answer and explanation
Answer: D (3 years)
Explanation
The total age falls from 30 × 15.3 = 459 to 30 × 15.2 = 456 years, so the boy is 3 years older than the girl.