The following data shows the heights and weights of the students of class 9. Which of the following is correct? Height Weight Mean 170 cm 55 kg Variance 130 cm2 25 kg2

Question

The following data shows the heights and weights of the students of class 9. Which of the following is correct?

         Height

Answer 1

The correct option is (a) Coefficient of variation of weights > Coefficient of variation of heights

Easy explanation: X̄1 = 170, X̄2 = 55, σ1^2 = 130 and σ2^2 = 25.

Now, Standard Deviation = √Variance

⇒ Standard deviation of height, σ1^2 = 130 ⇒ σ1 = √130 ⇒ σ1 = 11.40

and Standard deviation of weight, σ2^2 = 130 ⇒ σ2 = √25 ⇒ σ2 = 5

Also, Coefficient of Variance = (Standard Deviation/Mean) × 100

⇒ Coefficient of Variation in heights = (σ1/X̄1) x 100 = (11.40/170) x 100 = 6.7

and Coefficient of Variation in weights = (σ2/X̄2) x 100 = (5/55) x 100 = 9.09.