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3.1 Area under the curve, Part II: Z~N(μ = 0,σ = 1). (round answers to 3 decimal places)

a) Find x so that P(Z ≤ x) = 68%


b) Find the data value x at the 47th percentile


c) Find the data value x at the 50th percentile


Please give answers for all three questions. Thank you!

User AJ Tatum
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1 Answer

6 votes

Answer:

a.) 0.468

b.) -0.075

c.) 0

Explanation:

Given the distribution :

Z~N(μ = 0,σ = 1)

Distribution = normal

Mean (μ) = 0

Standard deviation (σ) = 1

a) Find x so that P(Z ≤ x) = 68%

Using the z probability calculator : Zscore corresponding to 68% = 0.68 = 0.468

Usingbthe relation :

Zscore = (x - m) / σ

0.468 = (x - 0) / 1

0.468 = x - 0

x = 0.468

b) Find the data value x at the 47th percentile

47th percentile = Zscore of - 0.075

Zscore = (x - m) / σ

-0.075 = (x - 0) / 1

-0.075 = x - 0

x = -0.075

c) Find the data value x at the 50th percentile

50th percentile = Zscore of 0.0

Zscore = (x - m) / σ

0.0 = (x - 0) / 1

0.0 = x - 0

x = 0

User Zengr
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