SOLUTION: Find the two standard scores(z) that correspond to the following. A) the middle 77% of a normal distribution is bound by them B) the middle 95% of a normal distribution is bound

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Question 852648: Find the two standard scores(z) that correspond to the following.
A) the middle 77% of a normal distribution is bound by them
B) the middle 95% of a normal distribution is bound by them
Thanks in advance!
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

Find z

A) the middle 77% of a normal distribution is bound by them

     23%/2 = 11.5%  NORMSINV(0.112)= -1.216,  z = ± 1.216

B) the middle 95% of a normal distribution is bound by them

     5%/2 = 2.5%  NORMSINV(0.025)= -1.96,   z = ± 1.96 (graph below)