OM5 Test Bank Supplementary Chapter A 1
APPENDIX 1
TRUE/FALSE
1. Job and process analysis should follow work measurement.
2. Normal time needs to be adjusted for personal time and avoidable delays.
3. The performance rating factor and allowances are based on human judgment.
4. Unavoidable delays should not be included in time studies.
5. A performance rating factor (PRF) of 130 percent means that a worker is slow and needs 30
percent more time.
6. For a time study, it is assumed that distribution of task times follows a Poisson distribution.
7. When timing a work activity with multiple tasks, the general rule is to take the largest sample
size estimate and use it for all activities or tasks.
8. Regression analysis is used to predict times based on different attributes of work.
9. Predetermined time standards are advantageous since they avoid needing multiple perfor-
mance ratings.
10. After developing a predetermined standard, stopwatch or work-sampling time studies need
not be performed.
11. The people best suited to set work standards are managers with input from industrial engi-
neers.
OM5 Test Bank Supplementary Chapter A 2
12. In the sample size for work sampling, “p” will never be known exactly since it is the popula-
tion parameter that is being estimated.
13. A 90 percent learning curve implies faster learning than an 80 percent learning curve.
14. The learning curve does not apply to supervisory personnel, some skilled craftspeople, or
jobs that have non-repetitive job tasks.
15. For an 80 percent learning rate, if the first unit requires 100 labor-hours, the 8th unit will re-
quire 64 hours.
MULTIPLE CHOICE
1. The outputs from a work measurement study lead to the development of labor and equipment
standards that are used for all of the following EXCEPT:
a.
estimating workforce capacity.
b.
determining fatigue and personal need allowances.
c.
determining the cost of new work procedures.
d.
providing accurate information for scheduling and sequencing.
2. A performance rating factor (PRF) of 1.15 means:
a.
a worker is working at a pace that is 15 percent faster than normal.
b.
a worker is working at a pace that is 15 percent slower than normal.
c.
a worker is working at a pace that is 15 percent faster than standard time.
d.
a worker needs to add 15 percent to the standard time.
3. Allowances include time for all of the following EXCEPT:
a.
fatigue.
b.
equipment breakdowns.
c.
rest periods.
d.
poor scheduling.
OM5 Test Bank Supplementary Chapter A 3
4. Personal fatigue and delay allowances are added to _____ to arrive at _____.
a.
standard time; normal time
b.
standard time; desired time
c.
normal time; desired time
d.
normal time; standard time
5. Which of the following is NOT part of the general approach to time study?
a.
Define and evaluate each task and activity.
b.
Measure and record the time needed to perform each activity over a number of cycles.
c.
Randomly observe work over a period of time to obtain a distribution of activities.
d.
Determine the allowance factor for the work activity.
6. All of the following are advantages of using regression analysis to determine standard time
EXCEPT:
a.
a smaller cycle time.
b.
the assumption of additive task times.
c.
statistically significant variables.
d.
confidence intervals for the prediction.
7. Predetermined time standards are _____.
a.
macromovements
b.
available in books and electronic tables
c.
a quick way to directly add up and get standard time
d.
best suited for old and stable manufactured goods
8. Work standards _____.
a.
improve motivation if set by managers
b.
increase variability if set by workers
c.
are best set informally
d.
work best when designed by workers
9. Work sampling _____.
a.
is based on normal distribution
b.
is used for repetitive work activities
c.
determines the proportion of time spent doing certain activities
d.
requires a systematic (non-random) sample to obtain a distribution of activities
10. A method of randomly observing work over a period of time to obtain a distribution of the
OM5 Test Bank Supplementary Chapter A 4
activities that an individual or a group of employees performs is called _____.
a.
learning curve analysis
b.
time study
c.
work sampling
d.
work measurement
11. All of following are true of learning curves EXCEPT:
a.
they are not used for a pricing strategy.
b.
they are affected by the ratio of manual to machine work.
c.
80 percent learning curves exhibit a step initial decline and then level off.
d.
they are used in defense industries.
12. The _____ states that the cost of doing any repetitive task, work activity, or project decreases
as the accumulated experience of doing the job increases.
a.
learning curve
b.
experience curve
c.
Deming philosophy
d.
regression method
13. Which of the following is NOT a practical issue when using learning curves?
a.
Incentive systems and bonus plans may increase learning.
b.
Complex, intellectual learning will be faster than learning simple tasks.
c.
A contract phaseout may result in a lengthening of process times.
d.
Keeping groups of employees together reaps a productivity benefit.
SHORT ANSWER
1. Define work measurement and what it leads to from an operations perspective.
2. Define and relate normal time and standard time.
3. Explain the use of regression analysis in establishing standard times with an example.
4. Define time study and describe the basic procedures for conducting a time study.
5. How are predetermined time standards useful?
6. Discuss the two different sides of the debate over work standards.
7. Define work sampling. Give examples of both manufacturing and service applications.
8. Explain the concept of learning curves using an 80 percent learning curve as an example.
9. Describe an experience curve.
10. Discuss several factors that can affect the applicability of the learning curve or experience
curve and/or the amount of learning that occurs.
OM5 Test Bank Supplementary Chapter A 7
PROBLEMS
1. Consider the following time study data.
Observation Cycles (Actual Time in Minutes)
Work
Task
1
2
3
4
5
6
7
A
0.12
0.17
0.19
0.11
0.15
0.16
0.20
B
0.91
0.95
0.97
0.88
0.86
0.80
0.94
C
1.52
1.48
1.40
1.60
1.65
1.52
1.47
a. If the performance rating factor for A = 1.15, B = 1.0, and C = 0.85, determine the normal time
for the job.
b. If personal allowance is 7 percent, fatigue allowance is 12 percent, personal delay allowance is
9 percent, and avoidable delay is 4 minutes, determine the standard time for the job.
2. A job had a normal time of 2.43 minutes, an allowance of 20 percent, and a forecast demand
of 120 units per day. How long should it take to produce one day’s output?
3. Consider the work sampling information below.
Work
Task
1
2
3
4
5
6
Q
25
30
27
31
22
20
R
40
52
35
42
47
38
S
60
62
50
55
62
58
a. If the performance rating factor for Q = 0.80, R = 1.10, and S = 1.10 and the total allowance is
17 percent, determine the normal time for the job.
b. With the allowance of 17 percent, determine the output per hour.
4. Based on data from a work-sampling study, an office worker spends 21.5 percent of his time
filing. Over the work-sampling period, he was idle 12 percent of the time. If the worker filed 420
items in a 40-hour workweek while performing other activities, and if his performance rating fac-
tor for filing was 0.95, determine the standard time, in minutes, he took to file an item.
5. An employee was observed over an extended period of time for a work-sampling study with
the following results:
Activity
Percentage of Time
Performance
Rating Factor
On the Phone
30
1.15
Filing
35
0.70
Face-to-Face with Customer
25
1.10
Idle
10
—–
While doing her job in a 40-hour workweek, the employee helped 120 face-to-face, walk-in cus-
tomers. Determine the standard time in minutes that it took her to help each customer.
6. Determine the sample size for the following time study given a standard deviation of four
minutes and a 98 percent probability that the value of the sample mean is within 1.5 minutes?
7. Determine the sample size for the following time study given a standard deviation of three
ounces and a 92 percent probability that the value of the sample mean is within two ounces?
OM5 Test Bank Supplementary Chapter A 9
8. For a work-sampling study, there is a 95 percent probability that the processing time of an ac-
tivity has an error of less than 0.06 minutes. The best estimate we have for “p” is 0.30. Deter-
mine the sample size needed for a work-sampling study if no estimate of “p” is available.
9. A yacht manufacturer signed a contract to build five sailboats for a California resort. Assuming
an 85 percent learning curve, how many labor-hours will it take to build all five sailboats if it took
7,000 standard hours to build the original sailboat?
10. A manufacturer made a commitment to supply 20 units of a product. The first unit took 1,200
hours to make, the second unit took 900 hours, and the third unit took 768 hours. How many
hours should it take to make the 20th unit?
11. A manufacturer made a commitment to supply 20 units of a product. The first unit took 1,200
hours to make, the second unit took 900 hours, and the third unit took 768 hours. Determine the
total number of hours required to make the first ten (10) items.
12. Locksmith Inc. has an order from a bank for 50 specially designed safes, one for each branch.
It is estimated that the first safe will require 75 hours of shop time and a 90 percent learning
curve is expected. The labor rate is $15.00 per hour and the pricing policy of the company is to
triple the labor cost of the order.
a. How many labor-hours should the 50th unit require?
b. How many labor-hours will the whole order require?
c. What is the customer’s price for each safe?
13. A company manufactures computer parts. They have received an order for 100 custom disc
drives. It is estimated that the first drive will take 20 hours of shop time and an 80 percent learn-
ing curve is expected. The labor rate is $15.00, and the pricing policy is to charge 3 times the la-
bor cost.
a. How many hours will the 100th disc drive take?
b. How many hours will the entire order take?
c. What is the price of the entire order?
d. What is the price per unit?
OM5 Test Bank Supplementary Chapter A 10
14. A company manufactures tractors and lawnmowers. They have received an order for six
deluxe custom riding lawnmowers for a local golf course. They must develop a cost estimate for
the order. It is estimated that the first lawnmower will take 90 hours of shop time and a 75 per-
cent learning curve is expected. The labor rate is $18.00 per hour, and the pricing policy of the
company is to charge 2.5 times the cost of labor for the order.
a. How many hours should the sixth lawnmower take?
b. How many labor-hours should the whole order take?
c. What is the customer’s price for the whole order?
d. What is the price per lawnmower?
e. If the original time estimate for the first lawnmower is too low, and it actually takes 80 hours
for the third lawnmower, what is the labor hour estimate for the first unit?
f. If it actually really takes 80 hours for the third lawnmower, what is the new total labor cost for
the entire order?
15. A furniture manufacturer has an order for 20 custom wine cabinets for a large hotel in Ha-
waii. It is estimated that the first cabinet will take 100 hours of shop time. An 85 percent learning
curve is expected. The labor rate is $12.00 per hour. The pricing policy is to charge two times the
labor cost for the order.
a. How many hours will the 20th wine cabinet take?
b. How many hours should the whole order take?
c. What is the price of each cabinet?
16. The Chester Table Company mass produces quality end tables for motels. They produce
5,000 end tables per week. The owner is trying to determine how many workers he needs. The
workers work 40 hours per week but are idle about three percent of the time because of the
cleaning of their area. Their performance rating is equal to one. The owner has developed these
OM5 Test Bank Supplementary Chapter A 11
time standards for operations per table:
Transporting the table through the plant = 2 minutes
Table top = 10 minutes
One leg = 4 minutes
Finishing = 5 minutes
a. How long does it take (in minutes) to produce one table?
b. What is the labor standard (in minutes) for this operation?
c. What is the minimum number of workers needed to produce 5000 tables in one week?
17. A fast-food stand has a thriving business in downtown Portland. They serve 3,500 burgers;
3,000 orders of fries; and 4,000 soft drinks per week. The workers work 40 hours per week but
are idle two percent of the time. The manager wants to try to become more efficient. He has
done a time study and found:
Elements for One Item
Minutes
Take order
2
Time taken for kitchen to fill
order
5
Pick up order & put in bag
1
Take customer’s money
2
It takes 1 additional minute per additional item. The average order size is 3 items.
a. What is the average number of orders per week?
b. What is the average cycle time (in minutes) per order?
c. What is the labor standard (in minutes) per order?
d. How many workers does the manager need per week?
18. The manager at a sewing factory uses a piece-rate pay system. She has just received an order
for 600 dresses from a discount house downtown. She is trying to figure out what her costs are
for the project. She has conducted a time study and found the following times for operations:
2 minutes to sew one sleeve
3 minutes to sew body of the dress
3.5 minutes to hem all unfinished edges
1 minute to attach the collar
3 minutes to attach all buttons
The workers must sit idle while they wait for supplies on the conveyor belt for an average of 30
seconds. Their performance rating is equal to one. She pays the workers $6.00 per hour.
a. What is the allowance factor for the operation?
b. What is the labor standard (in minutes) per dress?
c. What is the labor cost per dress?
d. What is the labor cost for the entire order of 600 dresses?