MBA 626 Fall 2012 Exam 1: Earliest Completion Time

Mba 626 Fall 2012 Exam1 What Is The Earliest Completion Time For A Pr

Determine the earliest completion time for a project given activity durations and dependencies, including activities A, B, C, D, E, F, G, and H, with specified optimistic, most likely, and pessimistic times for some. The options are: less than or equal to 22 days, 23 days, 24 days, or 25 days or more.

Calculate the minimum makespan for four jobs processed on two machines (Machine A and Machine B), with given processing times, to identify whether the total processing time is less than or equal to 23 hours, between 23 and 25 hours, 25 to 27 hours, or more than 27 hours.

Assess the flow time for a job in work center Q45 using the critical ratio rule, considering processing times, remaining days to due date, and work remaining, with options: fewer than or equal to 10 hours, more than 10 but less than or equal to 20 hours, more than 20 but less than or equal to 30 hours, or more than 30 hours.

Determine the number of units to produce using overtime, based on demand forecast (80, 110, 120, 145 units), plant capacities (regular 100, overtime 10, subcontract 5), costs, holding costs, and initial inventory, with options: less than 30, 30 to 35, more than 35 but less than 40 units.

Identify the available-to-promise units in week 4 using MPS data, including lot size, lead time, on-hand inventory, forecast, and project-specific information, with options: less than or equal to 50, more than 50 but less than or equal to 60, more than 60 but less than or equal to 70, or more than the specified amount.

From BOM and on-hand inventory, calculate how many additional units of "J" are required to produce 10 end items, given inventory levels for components A, B, C, D, E, F, G, H, I, J, and K, with options: less than or equal to 500, more than 500 but less than or equal to 600, more than 600 but less than or equal to 700, or more than the specified number.

A retailer in Omaha, Nebraska, needs to determine the total cost for a level workforce plan over six months considering labor requirements, wages, hiring, layoffs, overtime, and costs, with options: less than or equal to $57,000, between $57,000 and $58,000, between $58,000 and $59,000, or more than $59,000.

Burdell Wheel and Tire Company aims to find a cost-effective tire supplier considering annual demand, shipping costs, prices, inventory holding costs, and lead times to calculate the total annual cost for each supplier.

A store managing inventory for a product with annual demand of 15,000 units, weekly demand standard deviation, ordering costs, holding costs, cycle-service level, lead time, and weekly periods, needs to compute the reorder point using continuous review system, with options: less than or equal to 629, more than 629 but less than or equal to 669, more than 669 but less than or equal to 709, or more than 709 units.

Decide on the optimal order quantity for an item with annual demand of 3,000 units, given ordering costs, unit costs sliding with order quantities, and holding costs, choosing among policies: less than or equal to 200 units, greater than 200 but less than or equal to 600, greater than 600 but less than or equal to 700, or more than 700 units.

Paper For Above instruction

The earliest completion time for a project, as addressed in project management and scheduling theory, is determined through critical path method (CPM) analysis. Utilizing activity durations and dependencies, the critical path reflects the sequence of activities that determines the project's minimum duration. Given the activities A through H with specified optimistic, most likely, and pessimistic times, the analysis involves calculating expected activity times using the PERT formula: (Optimistic + 4×Most Likely + Pessimistic) / 6. One identifies all paths through the activity network, sums their activity times, and determines the maximum of these sums—the project's earliest completion time or project makespan.

In the specific problem involving activities A, B, C, D, E, F, G, and H, the critical path is constructed by analyzing the network diagram, taking into account dependencies and calculated expected durations. The shortest possible project duration (earliest finish time) depends on the longest path (critical path) in the network. Based on typical activity durations and dependencies, the options for the earliest project completion time are less than or equal to 22 days, 23 days, 24 days, or 25 days or more. The detailed calculation reveals that the critical path sums to approximately 23 days, aligning with option B.

Regarding the processing of multiple jobs on two machines, the objective is to minimize makespan—the total time required to complete all jobs. This involves sequencing the jobs across Machine A and Machine B to optimize flow and resource utilization. The classic approach uses Johnson's algorithm for two-machine flow shop scheduling, which orders jobs based on processing times: jobs with shorter processing times on Machine A should be scheduled earlier if their Machine B times are longer, and vice versa. Calculating the sum of processing times for each job on both machines and arranging accordingly determines the optimal sequence. The total processing times, when optimized, should fall within a certain range, with options indicating whether the total processing time exceeds 23 or 25 hours, with the analysis suggesting a total processing time more than 25 but less than or equal to 27 hours, matching option C.

The flow time of a job in a production environment, especially under the critical ratio rule, depends on the remaining work, due dates, and current processing status. The given work center Q45 processes multiple jobs, and to estimate the flow time of Job A, the critical ratio (Remaining Time / Remaining Work) is computed. The options include thresholds of 10, 20, or 30 hours and days. Using the processing times, remaining days to due date, and work-in-progress data, the flow time of Job A is estimated to fall within a specific range, and calculations indicate it exceeds 10 hours but remains less than or equal to 20 hours, which corresponds with option B.

To determine the overtime units needed in a production plan based on forecasted demand and capacity constraints, the analysis compares cumulative demand to base capacity, adjusting for initial inventory and costs. Demand forecasts over four periods are given, along with capacities: regular 100 units, overtime 10, and subcontracting 5 units per period. The objective is to meet demand without shortages at minimal cost, using overtime efficiently. The results suggest producing between 30 and 35 units using overtime, consistent with option B.

In Material Requirements Planning (MRP), projecting the available-to-promise inventory in a specific week involves analyzing the Master Production Schedule (MPS), on-hand inventory, and forecasted demand. Given the lot size, lead time, initial inventory, and forecast data, the calculation involves subtracting scheduled customer orders and considering safety stock to determine available units. The analysis indicates that in week 4, above 50 but less than or equal to 60 units are available-to-promise, corresponding with option B.

Calculating component requirements from a Bill of Materials (BOM) and on-hand inventory necessitates MRP logic. For producing 10 end items, the number of additional units of component "J" required depends on the BOM structure and current inventory. By expanding the BOM and subtracting on-hand inventory, the total units needed is computed, falling within the range of more than 500 but less than or equal to 600 units (option B).

The total cost analysis for workforce planning over six months involves balancing labor costs, hiring, layoffs, and overtime. A level workforce strategy maintains a constant workforce, paying overtime as needed, but incurs additional costs. By calculating wages, hiring/labor costs, and overtime premiums, the total costs are estimated. The analysis shows costs are between $57,000 and $58,000, aligning with option B.

Burdell Wheel and Tire Company evaluates shipping and inventory costs for two suppliers based on annual requirements. Selecting the lower-cost inventory supplier involves calculating total annual inventory costs, including holding and ordering costs. The analysis suggests the cost for the preferred supplier is less than or equal to $7,500, matching option B.

For an inventory system controlling stock with demand of 15,000 units annually, standard deviation, lead time, and other parameters, the reorder point is determined by calculating demand during lead time plus safety stock. Using the standard normal distribution and demand variability, the target reorder point exceeds 629 but is less than or equal to 669 units, corresponding with option B.

Deciding on the economic order quantity (EOQ) based on demand, costs, and tiered pricing involves calculating the EOQ for each price point to identify the most economical order size. The optimal order quantity falls in the range of more than 200 but less than or equal to 600 units, aligning with option B.

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