13 20 Selecting the best wafer-slicing machine. Silicon wafer slicing is a critical step in the production of semiconductor devices (e.g.. diodes, solar cells, transistors). Yuanpei (China) University researchers used control charts to aid in selecting the best silicon wafer-slicing machine (Computers & Industrial Engineering, Vol. 52, 2007). Samples of n = 2 wafers were sliced each hour for 67 consecutive hours and bow measurements (a measure of precision) were recorded. The resulting
- a. If the process is in control, what is the probability that a mean bow measurement for a randomly selected hour will fall above the upper control limit?
- b. If the process is in control, what is the probability that 3 of 67 mean bow measurements fall above the upper control limit?
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Statistics for Business and Economics (13th Edition)
- What is meant by the sample space of an experiment?arrow_forwardList the sample space of each experiment. Tossing three coinsarrow_forward5.6 When an audit must be conducted that involves a tedious examination of a large inventory, the audit may be very costly and time consuming if each item in the inventory must be examined. In such situations, the auditor frequently obtains a random sample of items from the complete inventory and uses the results of an audit of the sampled items to check the validity of the company's financial statement. A large company’s financial statement claims an inventory that averages $600 per item. The following data are the auditor’s assessment of a random sample of 75 items from the company’s inventory. The values resulting from the audit are rounded to the nearest dollar. 303 547 1,368 493 984 507 148 2,546 738 83 2 135 274 74 1,472 399 1,784 71 751 136 571 147 282 2,039 1,909 748 188 548 1 280 102 618 129 1,324 1,428 469 102 454 1,059 939 303 600 234 514 17 551 293 1,395 7 28 2…arrow_forward
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