The average height of three kids is 56 cm and their heights are in the proportion of 7 : 8 : 9. Find the heights of all the three.
Answer & explanation
Correct answer: option 4
Let's assume height of kids are 7x, 8x & 9x
So, 7x + 8x + 9x = 3 x 56
24x = 56 x3
x = 7
Accordingly, height of kids are 49, 56 & 63.