ISQS AFTER EXAM 2
Consider an activity that normally takes 14 weeks to complete at a cost of $3,300. The same activity can also be completed in 12 weeks at a cost of $4,000. What is the crash cost per week for the activity described here?
$350
Customers arrive to a convenience store server at the rate of 18 per hour. The customers form a single line in front of the store clerk. It takes the convenience store clerk (server) three minutes on average to complete service. What is the probability that any one customer will approach the store clerk and not have to wait (the probability of zero customers in the system)? The formula is: Probability of zero customers in line = 1 - arrival rate/service rate).
.1
Customers arrive to a convenience store server at the rate of 18 per hour. The customers form a single line in front of the store clerk. It takes the convenience store clerk (server) three minutes on average to complete service. What is the average waiting time in the queue, Wq, in hours? The formula is: Wq = Lq/arrival rate = arrival rate squared/(service rate*(service rate - arrival rate))/arrival rate
.45 hours
According to queueing theory, the work in process for a customer arrival rate of 18 customers/hour is 9 customers waiting in line and/or being served. According to Little's Law, Time in the system = work in process / throughput. What is the time in the system according to Little's Law?
.50 hours
Customers arrive to a convenience store server at the rate of 18 per hour. The customers form a single line in front of the store clerk. It takes the convenience store clerk (server) three minutes on average to complete service. What is the average waiting time in the system (waiting line plus service time)? The formula is: Lq = arrival rate squared/(service rate*(service rate - arrival rate))
.50 hours
Seven activities are to be considered for this problem. Additional information about these activities such as their activity time and immediate predecessors are included in the table that follows. Use this information to figure out the slack time for activity E. ActivityImmediate Predecessor(s)Activity Time(in weeks)ANone1BA1CA4DB5EB, C5FC1GD, E, F4
0
Harry, an executive manager at YingYang Inc., plotted the company's energy costs of $1 billion over the last 10 years. His chart implied the energy costs were increasing linearly and predictably. Further, the energy costs were dependent on time by the function, Y t = 10 + 3t. Y t represents the yearly energy cost in year t. Based on this linear equation, what is the value of the intercept that best fits the time series.
10
The auto loan division of a major bank wants to determine the size of the staff it would need to process up to 200 auto loan applications per day. It estimated that each loan officer can process a loan application in approximately 20 minutes. If the utilization of a loan officer is 0.8 (80 percent) and each loan officer works seven hours each day, how many loan officers (whole numbers) would be needed to handle that volume of business? Calculate first the service rate/day for any employee.
12
Seven activities are to be considered for this problem. Additional information about these activities such as their activity time and immediate predecessors are included in the table that follows. Use this information to figure out the earliest completion time (earliest finish) for this project using a Gantt or network chart. ActivityImmediate Predecessor(s)Activity Time(in weeks)ANone1BA1CA4DB5EB, C5FC1GD, E, F4
14 weeks
According to Little's Law, Time in the system = work in process / throughput. If it takes the convenience store clerk (server) three minutes on average to complete service, what is the throughput? Assume the WIP is 45 units.
15 customers
Customers arrive to a convenience store server at the rate of 18 per hour. The customers form a single line in front of the store clerk. It takes the convenience store clerk (server) three minutes on average to complete service. How many customers can the store clerk serve in one hour, to the nearest whole customer (i.e., the service rate per hour)?
20 customers
Ann has just launched by her company Adorable Apparel. She has determined the advertising for Adorable Apparel is an individual project consisting of 7 activities. Information pertinent to these activities is included in the table that follows. ActivityImmediate Predecessor(s)Activity Time(in weeks)ANone2BNone5CA8DA, B4EB6FC, D, E9GF10
30
Seven activities are to be considered for this problem. Additional information about these activities such as their activity time and immediate predecessors are included in the table that follows. Use this information to figure out the slack time for activity F. ActivityImmediate Predecessor(s)Activity Time(in weeks)ANone1BA1CA4DB5EB, C5FC1GD, E, F4
4
Seven activities are to be considered for this problem. Additional information about these activities such as their activity time and immediate predecessors are included in the table that follows. Use this information to figure out the latest finish time for activity C. ActivityImmediate Predecessor(s)Activity Time(in weeks)ANone1BA1CA4DB5EB, C5FC1GD, E, F4
5
What is the average time for a PERT task if the optimistic time is 30, the most likely time is 50 and the pessimistic time is 70?
50
Tammy, leads the advertising of an innovative product, Teckos, just launched by her company. She has determined the advertising for Teckos is an individual project consisting of 7 activities. Information pertinent to these activities is included in the table that follows. ActivityImmediate Predecessor(s)Activity Time(in weeks)ANone2BNone2CA4DB5EC5FD1GE, F2 Using a Gantt chart, determine the late start of Activity E.
6
Customers arrive to a convenience store server at the rate of 18 per hour. The customers form a single line in front of the store clerk. It takes the convenience store clerk (server) three minutes on average to complete service. What is the average length (# of customers) of the queue, Lq? The formula is: Lq = arrival rate squared/(service rate*(service rate - arrival rate))
8.1
Customers arrive to a convenience store server at the rate of 18 per hour. The customers form a single line in front of the store clerk. It takes the convenience store clerk (server) three minutes on average to complete service. What is the probability that any given customer has to wait, Pw? The formula is: Pw = arrival rate/service rate
9
If the number of arriving customers is 11 per minute and each of three servers is capable to accommodating 4 customers per minute, what is the utilization expressed as a %?
91.67
Which sentence harbors the most truth about a typical functional organization?
A project cuts across organizational boundaries in a typical functional organization.
Which of the following are discrete tasks which require resources and time, within the context of projects?
Activities
Helen has just launched by her company Forever Clothes. She has determined the advertising for Forever Clothes is an individual project consisting of 7 activities. Information pertinent to these activities is included in the table that follows. ActivityImmediate Predecessor(s)Activity Time(in weeks)ANone2BNone5CA8DA, B4EB6FC, D, E9GF10 Determine the critical path.
B-E-F-G
Of the choices provided, which can be defined as repeatable periods of ups and downs over relatively long periods of time (like several years), as it pertains to data patterns and variations in a time series?
Cyclical patterns
With time series data patterns in mind, which type of pattern can be described as regular upturns and downturns in a data series which occur over long periods of time?
Cyclical patterns
When are moving average (MA) methods most effective?
Demand is relatively stable and consistent.
Which of the following persons suggested that managers should use a throughput mentality rather than a cost mentality when making decisions and that doing so would force managers to identify bottlenecks, constraints?
Eli Goldratt
Which term describes the value achieved by subtracting the forecast value from the observed value in a time series?
Forecast error
Consider the functional area of information technology. Which of the following is an example of a project that belongs to that area?
Installing a revenue management system
Which of the options has the most utility for allocating budgets among divisions, scheduling jobs and resources, and planning workforce levels?
Intermediate-range forecasts
Which statement best characterizes the beta probability distribution approach within the framework of Project Evaluation and Review Technique (PERT)?
It allows managers to identify the best case, worst case, and most likely case for activity times.
Select the most accurate statement with regards to the Critical Path Method (CPM).
It assumes that activities are independent of one another, with clearly defined start and finish dates.
Suppose you were to crash a project. Which statement below is most accurate about your action?
It decreases the total duration of the project
Which of the following persons derived the formula that cycle time is equal to WIP divided by throughput?
John Little
What technique is used to predict future demands when historical data is unavailable?
Judgmental forecasting
Which of the options provided are associated with the effective planning of facility expansion?
Long-range forecasts
Which of the following persons recommended that managers obsess with their processes?
Michael Hammer
What should the value of the smoothing constant (α) be in an exponential smoothing model to be generally equivalent to a moving average model that has employed a 8-month moving average?
More than 0.20 but less than or equal to 0.25
What is the mean absolute deviation (MAD) for the forecasts in the provided table? MonthForecast DemandActual DemandApril100100May120125June150125July170160August220250
More than 10 but less than or equal to 15
Use the table provided to solve this problem. What is the mean absolute percentage error (MAPE) for the forecasts provided? MonthForecast DemandActual DemandApril4650May4550June5560July7080August7070
More than 5 percent but less than or equal to 10 percent
A single-server waiting line model makes all but which of the following assumptions?
One or more waiting lines (queues)
The district magistrate of Arkham City has decided to rebuild the busiest road in the city. She plans to close the street for the duration of the work, causing immense inconvenience to the people who typically use the road. The project has 3 parallel paths defined as the following: Path A-B-C-H will take 30 days. Path A-D-E-H will take 22 days. Path A-F-G-H will take 38 days. Given the information on hand, which of the following statements is true?
Path A-F-G-H is the critical path.
Which of the following persons wrote the book Quality is Free?
Philip Crosby
Which of the following topics is not covered in Chapter 11?
Process Improvement
Choose the term characterized as a temporary and often-customized initiative consisting of several smaller tasks and activities? It's necessary these tasks and activities are coordinated and completed in order to finish the whole initiative by its due date and within the allotted budget.
Project
Which method is used in the construction of a statistical model that establishes a relationship between one or more independent, numeric variables and one dependent, numeric variable?
Regression analysis
Which of the following are instrumental in the planning of production schedules and the assignment of workers to jobs by operations managers?
Short-range forecasts
Choose the forecasting technique used for forecasting the time series value in a subsequent period by employing a weighted average of previous time-series values.
Single exponential smoothing
Select the forecast or method that is rooted in the assumption future outcomes will be an extrapolation of previous observations.
Statistical forecasting
Consider the stages of the project management life cycle. Of those stages, which one incorporates responding to circumstances adversely impacting project participants, managing alterations to baselines, as well as gathering and analyzing status reports?
The controlling stage
Use the table of tube sock sales provided below to determine the forecast error in month 4 using a 3-month moving average. Assume each column's data are that of consecutive months. Month1234Sales118110105120
The forecast error in month 4 is more than 5 but less than or equal to 10.
The sales data for high-end staplers at an office store called Staplers are provided in the following table for the previous 5 years. After management plotted this data on a chart, it became clear the sales were predictably increasing in a linear manner. Further, the sales were dependent on time by the function, Y t = 1578 + 76t. Compute the forecasted sales in year 6 by utilizing simple linear regression. YearSales1165021700318504190051930
The forecast for sales in year 6 is more than 2000 but less than or equal to 2200.
When the time series in an exponential smoothing model produces a positive trend, the _______.
The forecast will undershoot the actual values
How is the slack time (ST) for an activity calculated? Answer this question using what you know of the Critical Path Method (CPM).
The latest finish (LF) time minus the earliest finish (EF) time
Which of the following dictates the duration of any project?
The longest path through the project network
A queueing system consists of three components. Which of the following is not one of those components?
The point-of-sale terminal
The table below illustrates the sales data for a specific model of a Blu-ray player. Assuming the forecast sales for May is 40.5, determine the sales forecast for July by applying a simple exponential smoothing (SES) model. Assume the value of the smoothing constant is 0.40. MonthSalesJan35Feb30Mar44Apr42May42Jun40
The sales forecast for July is more than 40 but less than or equal to 45.
Choose the most accurate statement regarding simple exponential smoothing. Assume the time series is relatively stable with minimal random variability.
Values of the smoothing constant larger than 0.5 place more emphasis on recent data.
While of the following persons strongly recommended prevention and training as methods for elimination of quality problems?
W. Edwards Deming
Utilization is calculated two ways. Which of the following is not one of those ways?
WIP divided by throughput
Customers arrive to a convenience store server at the rate of 18 per hour. The customers form a single line in front of the store clerk. It takes the convenience store clerk (server) three minutes on average to complete service. The store manager is thinking of adding a second server. Would you encourage him or her to do so? Why?
Yes, because no one will wait for 30 min in a convenience store
A typical approach used to collect data for judgmental forecasts is _______.
a survey questionnaire
A tracking signal offers the means to monitor a forecast by numerically representing _______.
bias
As it pertains to forecasting, _______ references a forecast's tendency to be larger or smaller than the actual values of a time series on a consistent basis.
bias
When there is a distinct trend in the time series (either up or down), the most accurate method to use is _______.
linear trend line