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प्रश्न
Variance of first 20 natural numbers is
विकल्प
32.25
44.25
33.25
30
उत्तर
33.25
Explanation;
Hint:
Variance of 20 natural numbers is
= `(20^2 - 1)/12`
= `(400 - 1)/12`
= `399/12`
= 33.25
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