For question 2, the goal is to make 569 fit into the first 2.5% on a bell curve.
According to the z-Score table, first 2.5% has the z-Score of -1.96.
μ = 605
x = 569
z = -1.96
Find σ
z-Score Formula:
z = (x - μ) / σ
Rearrange it to:
σ = (x - μ) / z
σ = (569 - 605) / -1.96
σ = 18.3673
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