Question

For a normal distribution, the estimated value of quartile deviation is 12. Find the value of its standard deviation.

Answer 1

Here, quartile deviation = 12
In normal distribution,

Estimated value of quartile deviation ≈ \(\frac{2}{3}\) σ

∴ 12 ≈ \(\frac{2}{3}\) σ

∴ σ ≈ \(\frac{12×3}{2}\) ≈ 18

Hence, the value of standard deviation obtained is 18.