Question

The total weight of 12 boys and 8 girls is 1080 kg. If the average weight of boys is 50 kg, then what will be average weight of girls?

• A. 55 kg
• B. 50 kg
• C. 60 kg
• D. 45 kg

Answer 1

Answer:

C. 60 kg

Solution: GIVEN: Total weight of 12 boys and girls is 1080 kg. Average weight of boys is 50 FORMULA USED: Weighted avg = (n1 × average of n1 quantity + n2 × average of n2 quantity + ----)/(n1 + n2 +------) CALCULATION: Total weight of boys and girls = 1080 kg Average weight of boys = 50 kg Let avg weight of girls be y 50 × 12 + 8 × y = 1080 ⇒ 8y = 1080 - 600 ⇒ 8y = 480 ⇒ y = 60 ∴ Average weight of girls is 60 kg