To find the cut off 37% from the bottom of z
scores.
The z scores are the standard normal variates with
a normal distribution.
So we have probabilty of z is
<= x such that this probability is 37%.
Therefore
P(z < = x) = 37%.
We know that Z has the standard
normal distribution. So P(z<=0) = 0.5.
Therefore
p(z > -x) = 0.37 = , as normal distribution is sy
mmetrical.
Therefore P(0 <= z< - x) =
0.5+(0.5-37) = 1-.37 = 0.63.
From normal probablity tables
, -x = 0.332. Or x = -0.332.
Therefore , the below cut
off 37% of the z scores is at z = -0.332 , or at z = -0.33 (rounded of to 2
decimals ).
No comments:
Post a Comment