Average weight of 25 boys in a class is 48 kgs. The average weight of the…
2023
Average weight of 25 boys in a class is 48 kgs. The average weight of the class of 40 students is 45 kgs. What is the average weight of the 15 girls in the class?
- A.
40
- B.
20
- C.
10
- D.
30
Attempted by 45 students.
Show answer & explanation
Correct answer: A
Solution: compute the total weights and then the average for the girls.
Total weight of 25 boys = 25 × 48 = 1200 kg.
Total weight of all 40 students = 40 × 45 = 1800 kg.
Total weight of 15 girls = 1800 − 1200 = 600 kg.
Average weight of the 15 girls = 600 ÷ 15 = 40 kg.