1. ## standard normal distribution

I have to find what separates the top 5% and the bottom 5% of the distribution. Mean is 9.75 and Standard dev is .08

I found that: -1.645= x - 9.75/ .08

I am terribly stuck as I already had found the area which was .95 looking at my chart of Positive and Negative z-scores but don't remember how to exactly find x.
I need some enlightenment, thanks so much. oH and do I have to draw the bell shaped curve as well?

2. Originally Posted by alexM0tts
I have to find what separates the top 5% and the bottom 5% of the distribution. Mean is 9.75 and Standard dev is .08

I found that: -1.645= x - 9.75/ .08

I am terribly stuck as I already had found the area which was .95 looking at my chart of Positive and Negative z-scores but don't remember how to exactly find x.
I need some enlightenment, thanks so much. oH and do I have to draw the bell shaped curve as well?
Top 5%, $\displaystyle P(z)=0.95$. This equals to 0.95-0.5 = 0.45.
I looked in the table for area = 0.45 and found z=1.645

$\displaystyle z=\frac{x-9.75}{0.08}$
$\displaystyle x=(1.645)(0.08)+9.75$

I cannot remember everything I have learned. That's why I peek in to remind me of it so that I could do well as I go upward.