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Statistics question

2020 · 4 Sep · Shift 2 · Q23
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Statistics question

2020 · 4 Sep · Shift 2 · Q23

JEE MainMathematicsStatisticsNumerical+4 / −1
If the variance of the following frequency distribution : Class : 10–20 20–30 30–40 Frequency : 2 x 2 is 50, then x is equal to ‾\underline{\hspace{2cm}}​
Numerical answer
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