The chair of the operations management department at Quality University wants to construct a p-chart for determining whether the four faculty teaching the basic P/OM course are in control with regard to the number of students who fail the course. Accordingly, he sampled 100 final grades from last year for each instructor, with the following results

Instructor	Number of Failures
Prof. A	13
Prof. B	0
Prof. C	11
Prof. D	16

What is the estimate of the mean proportion of failures for these instructors?

Group of answer choices

.10

.11

.13

.16

.40

A quality analyst wants to construct a control chart for determining whether four machines, all producing the same product, are in control with regard to a particular quality attribute. Accordingly, she inspected 1,000 units of output from each machine in random samples, with the following results

Machine	Total Defectives
#1	23
#2	15
#3	29
#4	13

For upper and lower control limits of .026 and .014, which machine(s), if any, appear(s) to be out-of-control for process proportion of defectives?

Group of answer choices

machine #3

machine #4

machines #3 and #4

machines #2 and #3

none of the machines