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Let X be normally distributed with mean = 16 and standard deviation = 12. Use Ta

ID: 3377669 • Letter: L

Question

Let X be normally distributed with mean = 16 and standard deviation = 12. Use Table 1. a. Find P(X 1).(Round "z" value to 2 decimal places and final answer to 4 decimal places.)   P(X 1)    b. Find P(X > 4). (Round "z" value to 2 decimal places and final answer to 4 decimal places.)   P(X > 4)    c. Find P(7 X 19). (Round "z" value to 2 decimal places and final answer to 4 decimal places.)   P(7 X 19)    d. Find P(10 X 19).(Round "z" value to 2 decimal places and final answer to 4 decimal places.)   P(10 X 19)   
Let X be normally distributed with mean = 16 and standard deviation = 12. Use Table 1.

Explanation / Answer

Normal Distribution
Mean ( u ) =16
Standard Deviation ( sd )=12
Normal Distribution = Z= X- u / sd ~ N(0,1)                  
a)
P(X < 1) = (1-16)/12
= -15/12= -1.25
= P ( Z <-1.25) From Standard Normal Table
= 0.1056                  
b)
P(X > 4) = (4-16)/12
= -12/12 = -1
= P ( Z >-1) From Standard Normal Table
= 0.8413                  
c)
To find P(a < = Z < = b) = F(b) - F(a)
P(X < 7) = (7-16)/12
= -9/12 = -0.75
= P ( Z <-0.75) From Standard Normal Table
= 0.22663
P(X < 19) = (19-16)/12
= 3/12 = 0.25
= P ( Z <0.25) From Standard Normal Table
= 0.59871
P(7 < X < 19) = 0.59871-0.22663 = 0.3721                  
d)
To find P(a < = Z < = b) = F(b) - F(a)
P(X < 10) = (10-16)/12
= -6/12 = -0.5
= P ( Z <-0.5) From Standard Normal Table
= 0.30854
P(X < 19) = (19-16)/12
= 3/12 = 0.25
= P ( Z <0.25) From Standard Normal Table
= 0.59871
P(10 < X < 19) = 0.59871-0.30854 = 0.2902