Let be a standard normal random variable. Use the calculator to determine the value of such that
P(-c

Question

Let  be a standard normal random variable. Use the calculator to determine the value of such that
P(-c<=Z<=c)=.9265

debbieg · Answer

Well, remember that the normal distribution is symmetric:
 |dw:1434763714199:dw|

anonymous · Answer

right so you divide it by 2

anonymous · Answer

now why did you add +.5?

debbieg · Answer

The area between the mean (0) and c is .9265/2. And the area to the left of the mean is 0.5. So you need c such that the area to the left of c (the total area) is 0.96325

debbieg · Answer

I think you use the inverse normal function in your calculator. I am not really familiar with doing them via calculator so I'd probably have to look up how to actually enter it... lol.

anonymous · Answer

lol we were actually taught on doing it on the calculator

anonymous · Answer

i think i would just do p(z<=.96325)

debbieg · Answer

Yes, that should work. I used invNorm(0.96325,0,1) and got 1.7897

debbieg · Answer

Can also use an online calculator like this one: http://stattrek.com/online-calculator/normal.aspx

anonymous · Answer

weird i got .8323