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Question
X is a normally distributed variable with mean µ = 30 and standard deviation σ = 4. Find P(30 < X < 35)
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Solution
Given X ~ N(µ, σ2)
µ = 30
σ = 4
P(30 < X < 35) = ?
When x = 30
z = `(35 - 30)/4 = 5/4` = 1.25
P(30 < x < 35) = P(0 < z < 1.25)
= 0.3944
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