Chapter 14: Q3BSC (page 654)
Control Limits In constructing a control chart for the proportions of defective dimes, it is found that the lower control limit is -0.00325. How should that value be adjusted?
The value of the lower control limit should be adjusted to 0.
Over 30 million students worldwide already upgrade their learning with Vaia!
All the tools & learning materials you need for study success - in one app.
Get started for free
Control Charts for p. In Exercises 5–12, use the given process data to construct a control chart for p. In each case, use the three out-of-control criteria listed near the beginning of this section and determine whether the process is within statistical control. If it is not, identify which of the three out-of-control criteria apply
Smartphone Batteries TheSmartBatt company manufactures batteries for smartphones. Listed below are numbers of defects in batches of 200 batteries randomly selected in each of 12 consecutive days of production. What action should be taken?
5 7 4 6 3 10 10 13 4 15 4 19
FAA Requirement Table 14-1 on page 655 lists process data consisting of the errors (ft) of aircraft altimeters when they are tested for an altitude of 2000 ft, and the Federal Aviation Administration requires that errors must be at most 30 ft. If x and R control charts show that the process of manufacturing altimeters is within statistical control, does that indicate that the altimeters have errors that are at most 30 ft? Why or why not?
What is the difference between random variation and assignable variation?
Energy Consumption. Exercises 1–5 refer to the amounts of energy consumed in the author’s home. (Most of the data are real, but some are fabricated.) Each value represents energy consumed (kWh) in a two-month period. Let each subgroup consist of the six amounts within the same year. Data are available for download at www.TriolaStats.com.
Jan.-Feb. | Mar.-April | May-June | July-Aug. | Sept.-Oct. | Nov.-dec. | |
Year 1 | 3637 | 2888 | 2359 | 3704 | 3432 | 2446 |
Year 2 | 4463 | 2482 | 2762 | 2288 | 2423 | 2483 |
Year 3 | 3375 | 2661 | 2073 | 2579 | 2858 | 2296 |
Year 4 | 2812 | 2433 | 2266 | 3128 | 3286 | 2749 |
Year 5 | 3427 | 578 | 3792 | 3348 | 2937 | 2774 |
Year 6 | 4016 | 3458 | 3395 | 4249 | 4003 | 3118 |
Year 7 | 4016 | 3458 | 3395 | 4249 | 4003 | 3118 |
Year 8 | 4016 | 3458 | 3395 | 4249 | 4003 | 3118 |
Energy Consumption:\(\bar x\)Chart Let each subgroup consist of the 6 values within a year. Construct an\(\bar x\)chart and determine whether the process mean is within statistical control. If it is not, identify which of the three out-of-control criteria lead to rejection of a statistically stable mean.
In Exercises 5–8, use the following two control charts that result from testing batches of newly manufactured aircraft altimeters, with 100 in each batch. The original sample values are errors (in feet) obtained when the altimeters are tested in a pressure chamber that simulates an altitude of 6000 ft. The Federal Aviation Administration requires an error of no more than 40 ft at that altitude.
What is the value of\(\bar \bar x\)? In general, how is a value of\(\bar \bar x\)found?
What do you think about this solution?
We value your feedback to improve our textbook solutions.
