Question

A sample of size 49 is randomly selected from a population with a mean, 25 and standard deviation, 14. Find P(X-bar > 26)

Answer 1

P(X>26)=0.4721

Explanation:

`Mean = \mu = 25`

Standard deviation =
`\sigma = 14`

No. of observations = n = 49

We are supposed to find
`P(\bar{X} > 26)`

`Z = (x-\mu)/(\sigma)\\Z=(26-25)/(14)\\Z=0.0714`

Refer the Z table for p value

P(X<26)=0.5279

P(X>26)=1-P(X<26)=1-0.5279=0.4721

Hence P(X>26)=0.4721