SOLUTION: Use the following formula: z = x − μ . σ IQ scores are well modeled by the normal model with a mean of 100 and a standard deviation of 16. What is the probabilit

Algebra ->  Probability-and-statistics -> SOLUTION: Use the following formula: z = x − μ . σ IQ scores are well modeled by the normal model with a mean of 100 and a standard deviation of 16. What is the probabilit      Log On


   

Question 1090493: Use the following formula: z = x − μ . σ
IQ scores are well modeled by the normal model with a mean of 100 and a standard deviation of 16. What is the probability that a randomly selected person has an IQ score:
(a) below 93?


(b) between 80and 104?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Find the z score,
z=%28x-mu%29%2Fsigma=%2893-100%29%2F16=-0.4375
P=P%28z=-0.4375%29
Find the probability from a normal distribution for this z value.
.
.
.
z%5B1%5D=%2880-100%29%2F16=-1.2
z%5B2%5D=%28104-100%29%2F16=0.25
So then,
P=P%5B2%5D-P%5B1%5D
P=P%28z=0.25%29-P%28z=-1.2%29