# Observations are adequate for this purpose determine

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observations are adequate for this purpose, determine the three-sigma control limits for dimples per camper top. UCLc= c ´ +z ´ c LCLc= c ´ -z ´ c Total Dimples is 7+9+14+11+3+12+8+4+7+6=81 Z=3 c ´ =total dimples/10=81/10=8.1 UCL=8.1+3* 8.1 =16.64 LCL=8.1-3* 8.1 =-0.44
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b. Suppose that the next camper top has 15 dimples. What can you say about the process now? Ans: Although 15 dimples is very high, it does not exceed the statistical range under the control of three sigmas. 4. Chapter 3, Problems, #31 – work only parts b) through d); the mean and the standard deviation for the data in Table 3.7 are 162.7 grams and 2.83 grams respectively. The data in Table 3.7 represents the results from the initial capability study 31. Beaver Brothers, Inc., is conducting a study to assess the capability of its 150-gram bar soap production line. A critical quality measure is the weight of the soap bars after stamping. The lower and upper specification limits are 162 and 170 grams, respectively. As a part of an initial capability study, 25 samples of size 5 were collected by the quality assurance group and the observations in Table 3.7 were recorded. After analyzing the data by using statistical control charts, the quality assurance group calculated the process capability ratio, Cp, and the process capability index, Cpk. It then decided to improve the stamping process, especially the feeder mechanism. After making all the changes that were deemed necessary, 18 additional samples were collected. The summary data for these samples are X ´ = 163 grams R ´ = 2.326 grams σ= 1 gram All sample observations were within the control chart limits. With the new data, the quality assurance group recalculated the process capability This study source was downloaded by 100000817023871 from CourseHero.com on 04-11-2021 04:08:02 GMT -05:00
measures. It was pleased with the improved Cp but felt that the process should be centered at 166 grams to ensure that everything was in order. Its
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