A normal population has a mean of 78 and a standard deviation of 6. You select a sample of 50.

Compute the probability the sample mean is: ( Round z values to 2 decimal places and final answer to 4 decimal places)

a) Less than 77

probability

b)Between 77 and 79

c) Between 79 and 80

d) Greater than 80

(a). z= x- mue/ sigma /sq rt (n) so for x = 77 , z= -1.18

Less than 77, P= 0.1190

(b). x= 79 , z = 1.18. and x= 77, z= -1.18

Between 77 and 79, P = 0.8810 -0.1190 =. 0.762

(c) x=80, z= 80-78/0.8485 = 2.36. and x= 79, z= 1.18

Between 79 and 80, P = 0.9909-0.8810. =. 0.1099

(d) x= 80 , P 1- 0.9909 = 0.0091

Please note answers required are in bold.

I have answered yurt question.

Niru

Secure Information

Content will be erased after question is completed.

Enter the email address associated with your account, and we will email you a link to reset your password.

Forgot your password?

Sign Up