Answer:
[tex] z=\frac{9.3-9.2}{\frac{1.6}{\sqrt{49}}}= 0.4375[/tex]
And we can use the normal table and the complement rule we got:
[tex] P(z>0.4375)= 1-P(z<0.4375) = 1-0.669= 0.331[/tex]
Step-by-step explanation:
For this case we have the following parameters given:
[tex]\mu = 9.2 , \sigma =1.6[/tex]
We select a ample size of n=49. And we want to find this probability:
[tex] P(\bar X> 9.3)[/tex]
And for this case is a right tail probability and we can use the z score formula given by:
[tex] z=\frac{\bar X -\mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
And replacing we got:
[tex] z=\frac{9.3-9.2}{\frac{1.6}{\sqrt{49}}}= 0.4375[/tex]
And we can use the normal table and the complement rule we got:
[tex] P(z>0.4375)= 1-P(z<0.4375) = 1-0.669= 0.331[/tex]