The average weight of all the 200 employees in an office is 68.2 kg, where $\frac{2}{5}$ of the employees are ladies and the ratio of the average weight of a man to that of a woman is 7 : 5. Find the average weight of the female employees.
Answer & explanation
Correct answer: option 3
Number of female employee = \(\frac{2}{5}\) × 200 = 80
Number of male employee = 200 - 80 = 120
Ratio of average weight of man to woman = 7 : 5
ATQ,
120 × 7R + 80 × 5R = 200 × 68.2 = 13640
840R + 400R = 13640
1240R = 13640
R = \(\frac{13640}{1240}\) = 11
Average weight of female employee = 5 × 11 = 55 kg