1. The local newspaper receives several complaints per day about typographic errors. Over a seven-day period, the publisher checks 100 paragraphs for errors (every day) and records the following number of errors: 4, 3, 2, 6, 7, 3, and 9. The publisher wants to construct a daily SPM chart to track changes in the probability of errors.

Based on the business information given, what type of control chart(s) should the publisher use?

a) p-chart

b) x-bar chart

c) R chart

d) x-bar and R-charts

2. You decide to track your daily coffee intake (in ounces) using a monitoring chart. Which of the following patterns is indicative of an out-of-control process (i.e. has assignable cause variation)?

a) 7 or more consecutive points above or below the centerline

b) 7 or more consecutive points oscillating above and below the centerline

c) A point that is above the upper control limit

d) All of the above

3. The probability of observing a point outside a three-sigma control chart (either above or below) is:

a) 5 percent

b) 3.4 per million

c) 3 per thousand

d) 97.23 percent

e) 2 percent

4. The X bar chart is to track changes in the:

a) gain or loss in uniformity of a product

b) percent defective in a sample across time

c) mean tendency of the process output across time

d) number of defects in a sample across time

e) within-sample variation of the process