The quality department at an electronics company has noted that, historically, 93% of the units of a specific product pass a test operation, 5% fail the test but are able to be repaired, and 2% fail the test and need to be scrapped. Due to recent process improvements, the quality department would like to test if the rates have changed. A recent sample of 500 parts revealed that 471 parts passed the test, 20 parts failed the test but were repairable, and 9 parts failed the test and were scrapped. (You may find it useful to reference the appropriate table: chi-square table or F table)

a. Choose the appropriate alternative hypothesis for the test.

multiple choice 1

• At least one of the p_i (i = 1, 2, 3) differs from its hypothesized value.

• All p_i (i = 1, 2, 3) values differ from its hypothesized value.

b-1. Compute the value of the test statistic. (Round the intermediate calculations to at least 4 decimal places and final answer to 3 decimal places.)

b-2. Find the p-value.

multiple choice 2

• p-value 0.10

• 0.05 p-value < 0.10

• 0.025 p-value < 0.05

• 0.01 p-value < 0.025

• p-value < 0.01

c-1. At the 5% significance level, what is your conclusion?

c-2. Would your conclusion change at the 1% significance level?

multiple choice 3

• No

• Yes