Given below is the observed data of the age of various boys. Study the table carefully and answer the question that follows.
| Age in years | Number of children (Boys) |
| 5 | 8 |
| 6 | 3 |
| 7 | 7 |
| 8 | 2 |
| 9 | 20 |
Calculate the mean age of the boys.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 7.57.
Sum of the ages = (5 × 8) + (6 × 3) + (7 × 7) + (8 × 2) + (9 × 20)
= 40 + 18 + 49 + 16 + 180
= 303
Total number of children = 8 + 3 + 7 + 2 + 20 = 40
Mean = 303/40 = 7.575 = 7.57 (approx)
Therefore, the mean age of the boys is 7.57 years.