Finding the percent is equal to find the probability:
[tex]P(5\leq X\leq11)[/tex]
in this normal distribution. To find this probability we need to use the z-score:
[tex]Z=\frac{x-\mu}{\sigma}[/tex]
Then we have:
[tex]P(5\leq X\leq11)=P(\frac{5-9}{2}\leq Z\leq\frac{11-9}{2})=P(-2\leq Z\leq1)[/tex]
Using the table given we have that:
[tex]P(-2\leq Z\leq1)=0.84134-0.02275=0.81859[/tex]
Therefore 81.9% of Haleys apples have between 5 and 11 seeds.
