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प्रश्न
If X ∼ N (4,25), then find P(x ≤ 4)
उत्तर
Given X ∼ N (4,25),
μ = 4, `sigma^2` = 25 `therefore sigma` = 5
Let Z = `(x - μ)/sigma`
then Z ∼ N (0,1)
P(X ≤ 4) = P `((x - μ)/sigma ≤ (4 - 4)/5)`
= P (Z ≤ 0)
P(X ≤ 4) = 0.5
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