a) A manufacturer of apple phone charges claims that only 4% of his production is defective. In a random sample of 120 items, the defect rate is 4.99%. At the 1% level of significance, test the manager's claim. i. State the null and alternative hypotheses for the test. ii. Calculate the value of the test statistic for this test. iii. Determine the critical region(s) for this test. iv. State the conclusion of this test. Give a reason for your answer.
Question One.
a) A manufacturer of apple phone charges claims that only 4% of his production is
defective. In a random sample of 120 items, the defect rate is 4.99%. At the 1% level of
significance, test the manager's claim.
i. State the null and alternative hypotheses for the test.
ii. Calculate the value of the test statistic for this test.
iii. Determine the critical region(s) for this test.
iv. State the conclusion of this test. Give a reason for your answer.
b) The table below shows the color and the model of cars purchased by 160 randomly
selected customers at a car dealership in 2020.
Model
Color Toyota Hyundai
Red 17 19
White 25 35
Black 35 29
Use a 5 percent level of significance to test the null hypothesis that color chosen and car model
are independent.
i. State the null and alternative hypotheses for this test.
ii. Calculate:
a. the expected frequency for red vehicle and the Toyota model
b. the chis-square contribution, ?2 for red vehicle and the Toyota model
i. Given that the chi-square test statistic, ?2, is 2.1183, find the p-value for test
ii. State the conclusion for the test.
iii. State 2 limitations of the chi-square test, ?2.
Trending now
This is a popular solution!
Step by step
Solved in 5 steps with 3 images
