Question 1

A work sampling study requires an acceptable error level of 10 percent and z = 2 for 95.45 percent confidence.The adequate sample size is ________ if the sample proportion is thought to be as large as 50 percent,but ________ if the sample proportion is thought to be about 20 percent.

Accepted Answer

The formula for calculating the required sample size for a work sampling study is:

n = z^2 * p * (1-p) / E^2

where 
z = critical value from the standard normal distribution for the desired level of confidence 
p = estimated proportion of time the activity being observed is occurring 
E = acceptable error level

For the first part of the question, where the sample proportion is thought to be as large as 50 percent, we can use p = 0.5. Thus,

n = 2^2 * 0.5 * (1-0.5) / (0.1^2) = 100

For the second part of the question, where the sample proportion is thought to be about 20 percent, we can use p = 0.2. Thus,

n = 2^2 * 0.2 * (1-0.2) / (0.1^2) = 64

Therefore, the best choice is B, where the adequate sample size is 100 if the sample proportion is thought to be as large as 50 percent, but 64 if the sample proportion is thought to be about 20 percent.

Question 2

Which of these is the most common predetermined time standard?

Accepted Answer

MTM (Methods-Time Measurement) is the most common predetermined time standard used by industries worldwide. It is a comprehensive system that analyzes each part of a task or job and assigns predetermined times to each component, resulting in a total standardized time for the task or job. This helps in planning and scheduling of work, setting production targets, and improving efficiency.

Question 3

A time measurement unit,or TMU,is:

Accepted Answer

The answer of A time measurement unit,or TMU,is:
...

Question 4

The accuracy of a labor standard is to be within ± 5%,and the confidence level is 95%.The standard deviation of the sample is 2 and the mean is 8.What sample size should be used?

Accepted Answer

The answer of The accuracy of a labor standard is...

Question 5

Suppose that the allowance factor for a job is 0.5 and the normal time is 5 hours.What is the standard time?

Accepted Answer

The answer of Suppose that the allowance factor for a...

Question 6

A manager who is conducting a time study now needs an accuracy of ±0.1 minutes,rather than ±0.2 minutes as in the past.Because of this change in accuracy,the new required sample size becomes:

Accepted Answer

The sample size required for a time study is inversely proportional to the square of the desired accuracy. Therefore, if we reduce the desired accuracy by half, we need four times as many observations to achieve the same level of precision. Therefore, if the desired accuracy is reduced from ±0.2 minutes to ±0.1 minutes, the required sample size increases by a factor of (0.2/0.1)^2 = 4.

Question 7

Which of the following techniques may NOT provide reliable and accurate labor standards?

Accepted Answer

Historical experience may not always provide reliable and accurate labor standards because it relies on past data that may not account for changes in technology, processes, or worker skill levels. Methods like MTM, time studies, work sampling, and predetermined time standards are more systematic and analytical, thus generally considered more reliable for setting labor standards.

Question 8

Therbligs:

Accepted Answer

Therbligs were named by Frank Gilbreth and were used during the scientific management era. They are still used today as a way to identify and eliminate unnecessary motions in the workplace. Choice A is incorrect as Taylor is often associated with scientific management, but he did not invent therbligs. Choice B is incorrect as therbligs are still relevant and used today. Choice C is incorrect as it is not a valid definition of therbligs. Choice E is incorrect as therbligs are not a unit of time.

Question 9

Which of the following is not a method used to set labor standards?

Accepted Answer

The answer of Which of the following is not a...

Question 10

Sample observations of a claims processor made over a 160-hour work month reveal that the worker produced a total of 384 completed claims forms.The performance rating was 80%.The worker was idle 20% of the time (so that idle time should be subtracted from the total time when computing the average observed time).The allowance factor is 8%.What is the standard time per unit?

Accepted Answer

Standard time per unit = average observed time / (1 - allowance factor)
Average observed time = total time worked / number of units completed
Total time worked = 160 hours - (0.20 x 160 hours) = 128 hours
Number of units completed = 384
Average observed time = 128 hours x 60 minutes/hour / 384 units = 20 minutes/unit
Standard time per unit = 20 minutes / (1 - 0.08) = 17.4 minutes. 
Therefore, the best choice is C, which matches the calculated standard time per unit.

Question 11

Timing a sample of a worker's performance and using it as a basis for setting a standard time describes which of the following?

Accepted Answer

Timing a worker's performance and using it as a basis for setting a standard time is commonly referred to as time studies. This method involves breaking down a task into smaller parts, timing each part, and determining an average time for the entire task. This average time can then be used as a standard time for that task, allowing for more accurate scheduling and workload planning.

Question 12

Normal time for a stopwatch study is equal to which of the following?

Accepted Answer

Normal time is calculated by multiplying the average observed time by the performance rating factor. This accounts for the worker's performance relative to the standard performance level.

Question 13

Which of the following is NOT a use of labor standards?

Accepted Answer

The answer of Which of the following is NOT a...

Question 14

The smaller the percentage established for allowances:

Accepted Answer

Allowances are additional time added to normal time to account for factors such as fatigue, personal needs, and unavoidable delays. A smaller percentage established for allowances would mean that normal time is closer to standard time, which is the time required to perform a task without any allowances. Therefore, the answer is A.

Question 15

The average observed time for a given job is 10 minutes.The performance rating is 80%,and allowances are set by contract at 10%.What is the standard time?

Accepted Answer

Standard time = average observed time / (performance rating + allowances)
= 10 / (0.8 + 0.1)
= 10 / 0.9
= 11.11 minutes (rounded to nearest hundredth)
However, since the allowances are set at 10%, we need to subtract that from the standard time to get the final answer:
Standard time - allowances = 11.11 - (0.1 x 11.11) = 11.11 - 1.11 = 10 minutes
Therefore, the standard time is 10 minutes, which corresponds to choice B.

Question 16

The data below represent time study observations for an assembly operation.Assume a 7% allowance factor.What is the normal time for element 3?

Accepted Answer

The answer of The data below represent time study observations...

Question 17

In time studies,personal time allowances are often established in which of the following ranges?

Accepted Answer

Personal time allowances are established to account for personal needs such as rest, fatigue, and personal interruptions that may occur during the work process. The range of personal time allowances can vary based on the nature of the work, the health of the worker, and the environment in which the work is performed. However, the range of 4 - 7% is commonly used in time studies as it provides enough allowance for personal needs while still maintaining a high level of productivity.

Question 18

A worker completed a task 10 times during a period in which a typical trained employee completes the task 8 times.What is the worker's performance rating?

Accepted Answer

The answer of A worker completed a task 10 times...

Question 19

Sample observations of a claims processor made over a 160-hour work month reveal that the worker produced a total of 384 completed claims forms.The performance rating was 80%.The worker was idle 20% of the time (so that idle time should be subtracted from the total time when computing the average observed time).The allowance factor is 8%.What is the normal time per unit?

Accepted Answer

The answer of Sample observations of a claims processor made...

Question 20

In time studies,normal time is:

Accepted Answer

Normal time is calculated by multiplying the average observed time by a performance rating factor to adjust for the worker's performance level.

Quiz 10: Human Resources,job Design,and Work Measurement

A work sampling study requires an acceptable error level of 10 percent and z = 2 for 95.45 percent confidence.The adequate sample size is if the sample proportion is thought to be as large as 50 percent,but if the sample proportion is thought to be about 20 percent.