Question

If continuous random variable X is normally distributed, with u = 8.7 and 0 = 3.9, what isPIX > 14)?O 12.30%8.69%87.70%91.31%

Answer 1

SOLUTION

$\begin{gathered} Z\text{ = }\frac{x-\mu}{\sigma}\text{ } \\ \text{Where Z = z-score, x = observed value, }\mu=\text{sample mean, }\sigma\text{ = standard deviation} \\ Z\text{ = }\frac{14-8.7}{3.9}=1.36\text{ } \\ Z\text{ score becomes } \\ (P>)\text{ = 0.087} \\ =\text{ 8.69} \\ \end{gathered}$

The answer = 8.69%, the second option