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.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 49 cm, 56 cm, 63 cm.
Calculations:
The Sum of the height of 3 kids = 56 × 3 = 168
Let the height of three kids be 7x, 8x and 9x.
According to the question;
⇒ 7x + 8x + 9x = 168
⇒ 24x = 168
⇒ x = 7
Hence the height of all three
⇒ 7x = 7 ×7 = 49 cm
⇒ 8x = 8 × 7 = 56 cm
⇒ 9x = 9 × 7 = 63 cm