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प्रश्न
Choose the correct alternative :
If X ∼ B`(20, 1/10)` then E(X) = _______
विकल्प
2
5
4
3
उत्तर
Given,
X ∼ B`(20, 1/10)`
∴ Here, n = 20 and p = `(1)/(10)`
∴ E(x) = np = `20 xx (1)/(10)` = 2.
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