The average age of 3 girls is 24 years and their ages are in the proportion of 7 : 8 : 9. What is the age of the eldest girl?
The average age of 3 girls is 24 years and their ages are in the proportion of 7 : 8 : 9.
Let's assume the ages of 3 girls are 7y, 8y and 9y.
$$\frac{7y+8y+9y}{3}\ =\ 24$$
$$24y\ =\ 72$$
y = 3Age of the eldest girl = 9y
=Â $$9\times3$$
= 27 years
Create a FREE account and get: