In a class, the average weight of 20 girls is 60 kg, while the average weight of the remaining 16 girls is 45 kg. What is the average weight of all the girls in the class?
Show answer & explanation
Correct answer: B
Explanation
Given:
Average of 20 girls = 60 kg
Average of 16 girls = 45 kg
According to the formula:
Average = (Total Weight) / (Total Number)
Total weight of the first group = 20 × 60 = 1200
Total weight of the second group = 16 × 45 = 720
Total weight = 1200 + 720 = 1920
Total number = 20 + 16 = 36
Average = 1920 / 36 ≈ 53.33 kg