Question 136632
3. The same production manager in question 1 above decides to use a smaller sample size of just 25 items. If she conducts a 2-tailed test at the 90 percent level of confidence, her critical value(s) would be: t = 1711
---------------------------------------------------------
4. National Packing Materials Company claims its X20 box can hold loads up to at least 80 pounds. Smith Widget Company has been using the boxes for one year and feels the boxes fail at lighter loads. Hearing the complaints from Smith, the lead engineer for National Packaging decides to test the company’s claim that it can hold at least 80 pounds. He decides to test 64 boxes at the .05 level of significance. He finds a mean of 78 pounds with a standard deviation of 5 pounds. 
What is the critical value for this test? z= 1.645_______ 
What is the value of the test statistic? -3.2___________ 
What is the Null hypothesis? u=80___________ 
What is the alternate hypothesis? u>80____________ 
What is the standard error of the mean? E=1.645*[5/sqrt(64)] = 1.028125.. ______________ 
Should the Null hypothesis be accepted or rejected? Reject Ho __________
================
Cheers,
Stan H.