Find $\mathrm { P } ( \bar { X } 172 )$ If ? = 175 and $\sigma _ { \bar { X } } ^ { 2 } = 9$
A).1587
B).8413
C).6293
D).3707

Name: Find $\mathrm { P } ( \bar { X } > 172 )$ If ? = 175 and $\sigma _ { \bar { X } } ^ { 2 } = 9$ A).1587 B).8413 C).6293 D).3707
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Question

Find $\mathrm { P } ( \bar { X } > 172 )$ If ? = 175 and $\sigma _ { \bar { X } } ^ { 2 } = 9$
A).1587
B).8413
C).6293
D).3707

Quizplus · Accepted Answer

The standard deviation of the sample mean is the square root of the variance, which is 3. The z-score is (172-175)/3 = -1. The probability of a z-score greater than -1 is 0.8413.

Find P(Xˉ>172)\mathrm { P } ( \bar { X } > 172 )P(Xˉ>172)

Find $\mathrm { P } ( \bar { X } > 172 )$