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

Answer:

P(X>26)=0.4721

Step-by-step explanation:

$Mean = \mu = 25$

Standard deviation = $\sigma = 14$

No. of observations = n = 49

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

$Z = \frac{x-\mu}{\sigma}\\Z=\frac{26-25}{14}\\Z=0.0714$

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