Question 581394:  The mean SAT math reasoning score in 2009 was 515.3 with a standard deviation of 114.1. An educational psychologist believes that students who take at least 4 years of English in high school perform better on the exam.  To test the hypothesis, she obtains a random sample of 40 student (with 4 years of English) and their mean score was 540. Test the claim at "alpha" = 0.05.
 
I am so lost on this one. 
 
Thank you 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! The mean SAT math reasoning score in 2009 was 515.3 with a standard deviation of 114.1. An educational psychologist believes that students who take at least 4 years of English in high school perform better on the exam. To test the hypothesis, she obtains a random sample of 40 student (with 4 years of English) and their mean score was 540. Test the claim at "alpha" = 0.05.  
------- 
Ho: u <= 515.3 
Ha: u > 515.3 (claim) 
----- 
z(540) = (540-515.3)/[114.1/sqrt(40)] = 1.3691 
------- 
p-value = P(z > 1.3691) = 0.0855 
------ 
Since the p-value is greater than 5%, fail to reject Ho. 
--- 
The test results do not support the claim. 
=============================================== 
Cheers, 
Stan H. 
================= 
  | 
 
  
 
 |   
 
 |