Question:

If \(\mu_1,\mu_2\) and \(\mu_3\) are the mean, median and mode respectively of a normal distribution, then \[ 3(\text{Median})-2(\text{Mode}) = ? \]

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Remember the standard empirical relation: \[ \text{Mode}=3(\text{Median})-2(\text{Mean}). \] It is one of the most important formulas in descriptive statistics.
Updated On: Jun 25, 2026
  • \(\mu_1\)
  • \(\mu_2\)
  • \(\mu_3\)
  • \(0\)
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The Correct Option is A

Solution and Explanation

Concept: For a moderately skewed distribution, the empirical relationship among mean, median and mode is \[ \text{Mode} = 3(\text{Median}) - 2(\text{Mean}). \] This relation is one of the most frequently used results in statistics. For a normal distribution specifically, \[ \text{Mean}=\text{Median}=\text{Mode}, \] and the empirical relation is also satisfied.

Step 1:
Write the empirical relation.
\[ \text{Mode} = 3(\text{Median}) - 2(\text{Mean}). \] Using the notation of the question, \[ \mu_3 = 3\mu_2 - 2\mu_1. \]

Step 2:
Rearrange the expression.
Transposing terms, \[ 2\mu_1 = 3\mu_2-\mu_3. \] Therefore, \[ \mu_1 = \frac{3\mu_2-\mu_3}{2}. \] For a normal distribution, \[ \mu_1=\mu_2=\mu_3. \] Hence, \[ 3\mu_2-2\mu_3 = \mu_1. \]

Step 3:
Substitute the required expression.
The quantity asked is \[ 3(\text{Median})-2(\text{Mode}) = 3\mu_2-2\mu_3. \] Using the relation above, \[ 3\mu_2-2\mu_3 = \mu_1. \] Therefore, \[ \boxed{\mu_1} \]
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