\(OA Explanation\)

In ND,
Maximum value = \(X̄ + 3σ\)
Minimum value = \(X̄ - 3σ\)

Where, \(X̄\) is mean and \(σ\) is standard deviation

So,
\(X̄ + 3σ = 75\)
\(X̄ - 3σ = 45\)

\(2X̄ = 120\)
\(X̄ = 60\)

Col. A = Col. B
Hence, option C

Hi KarunMendiratta

I see OA as A. Could you please update the same to C

Kind Regards

Ks1859
Thanks for pointing out, I have edited the OA.

For this problem, I solved it by finding the average of the highest and lowest values:

(Highest # + Lowest #)/(2) = Mean

(75 + 45)/2 = 60

Answer C:

The aforementioned formula is simply a rearrangement of the formula used by previous authors on this thread:

Maximum value = \(X̄ + 3σ\)
Minimum value = \(X̄ - 3σ\)