SOLUTION: he standard iq test has a mean of 96 and a standard deviation of 14. We want to be 90% certain that we are within 4 IQ points of the true mean. Determine the required sample size
Algebra ->
Probability-and-statistics
-> SOLUTION: he standard iq test has a mean of 96 and a standard deviation of 14. We want to be 90% certain that we are within 4 IQ points of the true mean. Determine the required sample size
Log On
Question 1143470: he standard iq test has a mean of 96 and a standard deviation of 14. We want to be 90% certain that we are within 4 IQ points of the true mean. Determine the required sample size.
a, 1
b. 6
c. 34
d. 130 Answer by amarjeeth123(570) (Show Source):
You can put this solution on YOUR website! We have,
z=1.64 for a confidence interval of 90%
sigma=14
CI=4
CI=z*sigma/sqrt(n)
Plugging in the values we get,
4=1.64*14/sqrt(n)
sqrt(n)=(1.64*14/4)=5.74
n=32.9 which is approximately 34.
Answer=(c)34
(