Suppose Harvey owns a small business that produces computer motherboards. He previously owned one machine, machine A, that produced these motherboards. In an effort to increase production, he recently purchased a new machine, machine B, that also produces motherboards. Although both machines produce motherboards at the same rate, Harvey suspects that machine A produces fewer defective motherboards than machine B. In order to test this hypothesis, he randomly selects 260 motherboards produced by machine A and 200 motherboards produced by machine B. He observes that 13 of the sampled items from machine A are defective and 14 sampled items from machine B are defective. Harvey plans to use the sample data he collected to test if the frequency of defective items produced by machine A is less than the frequency of defective items produced by machine B. Select the appropriate test that Harvey should perform to test his hypothesis.
a. two-sample t-test for two means
b. one-sample z-test for a mean
c. one-sample z-test for a proportion
d. matched-pairs t-test
e. two-sample z-test for two proportions