Use the normal distribution of SAT critical reading scores for which the mean is 515 and the standard deviation is 118. Assume the variable x is normally distributed. a)What part of the SAT verbal scores is less than 625?

Question

Use the normal distribution of SAT critical reading scores for which the mean is 515 and the standard deviation is 118.  Assume the variable x is normally distributed. a)What part of the SAT verbal scores is less than 625?

jim_thompson5910 · Answer

do you have a TI calculator?

anonymous · Answer

It really depends on what you are using to calculate the cumulative distribution function.

anonymous · Answer

If you are using Z-tables $\Phi(z)$ then  $$
z = \frac{X-\mu}{\sigma}
$$

anonymous · Answer

$$
z = \frac{625-515}{118}\
\Pr(X\leq625) = \Phi\left(\frac{625-515}{118}\right)
$$