JEE Main · 2023 · 10 Apr 2023 · Shift 1 · Statistics

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If the mean of the frequency distribution

\begin{tabular}{|l|l|l|l|l|l|}
\hline Class: & & & & & \\
\hline Frequency & 2 & 3 & x & 5 & 4 \\
\hline
\end{tabular}

is 28 , then its variance is ____.

Answer: 151

Solution

The mean is given by , where are class marks: 5, 15, 25, 35, 45.







Variance = :

JEE Main · 2023 · 10 Apr 2023 · Shift 1 · Integer answer

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