a Actual average time is 79 seconds b Normal time is 79 120 948 seconds c

A actual average time is 79 seconds b normal time is

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a. Actual average time is 79 seconds. b. Normal time is 79 * 1.20 = 94.8 seconds. c. Standard time is 94.8 / (1-.14) = 110.23 seconds. d. The revised standard time is 94.8 / (1-.20) = 118.5 seconds. (Time studies, difficult) {AACSB: Analytic Skills} 62. A task involves positioning two metal parts with a rubber gasket sandwiched between them, inserting two bolts into predrilled holes, threading a nut onto each bolt, and tightening each bolt with a pneumatic wrench. In a preliminary study, the manager observed one of his workers perform this task five times. The observations were made in an air-conditioned, well-lighted training facility, at ground level, with all tools and equipment clean and readily available. Observation: 1 2 3 4 5 Task time (seconds): 50 54 60 145 56 a. What is the average observed time for this task? b. What is the normal time for this task if the employee worked at a 10% slower pace than is typical for adequately trained workers? c. What is standard time for this task if allowances are 8% constant and 6% variable? Note that the fourth time must be discarded as an unusual event. a. Actual observed time is 220 / 4 = 55 seconds. b. Normal time is 55 * 0.90 = 49.5 seconds. c. Standard time is 49.5 / (1-.14) = 57.6 seconds. (Time studies, difficult) {AACSB: Analytic Skills}
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63.The data in the following table represent time-study observations on a new operation with three work elements. On the basis of these observations, find the standard time for the process. Assume a15% allowance factor.Observations (times in seconds)ElementPerformance Rating12341120%90.391.592.490.22100%30.532.329.631.13105%130.5128.9132130.5 Answer: Observations (times in seconds) Element Rating 1 2 3 4 Average Normal Time 1 120% 90.3 91.5 92.4 90.2 91.10 109.32 2 100% 30.5 32.3 29.6 31.1 30.88 30.88 3 105% 130.5 128.9 132 130.5 130.48 137.00 Normal time for process = 109.32 + 30.88 + 137.00 = 277.20 seconds seconds 326.12 = 15 . 1 20 . 277 fraction Allowance - 1 time Normal job for time Standard (Time studies, moderate) {AACSB: Analytic Skills}
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64. An operation in a television factory has an average observed time of 6 minutes. The performance rating of the worker timed was estimated at 90%. Practice in this department is to allow 8% for the constant allowances. Currently, there is no variable allowance. a. Find the normal time for the operation.b. Compute the standard time for the operation.c. Recompute the standard time if a variable allowance of 8% is factored in. a. Normal time = 6 minutes * .90 = 5.4 minutes b. minutes 5.87 = 08 . 0 1 4 . 5 factor Allowance - 1 time Normal time Standard c. minutes 6.43 = 16 . 0 1 4 . 5 factor Allowance - 1 time Normal time standard New (Time studies, moderate) {AACSB: Analytic Skills} 65. An initial analysis of a laboratory activity resulted in the first table below. After this analysis, the managers determined that their element descriptions were not as accurate as they should have been —they had left out an element, underestimated a distance, and understated the need for accuracy. They revised the table of element data, which appears in the second table. Original Activity: Pouring tube specimen Element description Element code TMU Get tube from rack AA2 35 Get stopper, place on counter AA2 35 Get centrifuge, place at sample tube AD2 45 Pour (3 sec.) PT 83 Place tubes in rack (simo) PC2 40 TOTAL TMU Revised Activity: Pouring tube specimen Element description Element code TMU
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