# Public Toilet

### Public Toilet

G answer B F A 1) J I C E D 2) Cycle Time (CT) = Productive time per hour Output per day = 7 hrs. /day X 60 min/hr X 60 sec/min 1008 units/day = 25,200 sec 1008 units = 25 sec/unit 6 5 4 3 2 1 3) Workstation = J I G H F E C D B A

Task Time 24 25 25 25 25 24 Idle Time = 1 0 0 0 0 1 ( Total = 2 sec ) 4) WS = Sum of task times Cycle time (CT) = 148 sec 25 sec/units = 5. 2 ? 6 units of WS 5) Efficiency = Sum of task times X 100% CT * Actual # of (WS) = 148 sec * 100 % ( 25 sec/units * 4 units of WS) = 98. 67 % ) Idle time per units = (CT * actual # of WS) – sum of task times = (25 sec/unit X 6 units of WS) – 148 seconds = 2 sec/units Idle time in seconds per day = idle time per units X output per day (in unit) = 2 sec/unit X 1008units/day = 2016 sec/day Idle time in hour per day = Idle time in seconds per day 60 min/hr X 60 sec/min = 2016 sec/day 60 min/hr X 60 sec/min = 0. 56 hr/day Thus,

The cost of idleness per week = Idle time in hour per day X wage rate per hour X # working day per week = 0. 56 hr/day X RM 40 per day = RM 22. 40 per week QUESTION 4 Claytan Fine China, a well-known dinner ware producer has upgraded its moulding procedure by using the most sophisticated equipment. The mouding process consists of 10 elements. The following table shows the task element in alphabetical order and their precedence element task(s) and times in seconds.

Task Element| Precedence Task| Task Time (seconds)| A| -| 24| B| A| 25| C| A| 13| D| -| 10| E| C, D| 12| F| B, E| 11| G| B| 15| H| -| 14| I| F,G. H| 10| J| I| 24| 1. Draw a precedence diagram 2. If the expected weekly output is 5040 dinner sets and daily productive time is 7 hours (in a 5 day work-week), compute the cycle for the process. 3. Compute the theoretical number of workstations. 4. Arrange the task element into proper workstations by using the longest task-time heuristic/rule. 5. Calculate the efficiency of the balanced line and balance delay. 6. If the wage rate is RM 40 per day, calculate the idleness cost per week.

QUESTION 8 Hakim Bidaman Enterprise is in the process of developing an aggregate capacity plan for the month of Jan-Sept 2010. The company has gathered the data as shown in the following table: MONTH| Jan| Feb| Mar| Apr| May| Jun| Jul | Aug| Sept| Forecast Demand (unit)| 5000| 4900| 4500| 4200| 6300| 5000| 5100| 4800| 4700| Other information to be considered: 1. Each output requires 26 minute to be produced. 2. Labour cost per hour is RM 5. 00 3. Overtime rate per hour is RM 7. 50 4. Overtime given to 4 workers only with a limitation of 2 hours per day. 5. Beginning inventory is 400 units. . The inventory carrying cost is RM 2. 40 per unit. 7. Hiring cost per worker is RM 400 and lay off cost per worker is RM 600 8. Subcontracting cost is RM 20 per unit. 9. Current workforce level is 10 workers. 10. The company operates 8 hours daily in 26 days a month. Determine the production cost for the planning horizon by using all five strategies. Apply information given as necessary for a certain strategy. ANWER STRATEGY 1 Monthly forecast output = number of day per monthly X daily standard output = 26 days (60 minutes/hr ? 6 minutes/unit X 8 hours/day) = 480 units per worker per month MONTH| FORECASTDEMAND (UNIT)=UNIT PRODUCED| CURRENT WORKER| WORKERS REQUIRED| HIRE| LAY OFF| Jan| 5000 – 400 = 4600| 10| 4600/480 = 10| | | Feb| 4900| 10| 4900/480 = 10| | | Mar| 4500| 10| 4500/480 = 9| | 1| Apr| 4200| 9| 4200/480 = 9| | | May| 6300| 9| 6300/480 = 13| 4| | Jun| 5000| 13| 5000/480 = 10| | 3| Jul| 5100| 10| 5100/480 = 11| 1| | Aug| 4800| 11| 4800/480 = 10| | 1| Sept| 4700| 10| 4700/480 = 10| | | | 44100| | | 5| 5| TOTAL PRODUCTION COST Regular production cost = (44100 units) X (RM5/hr) X (26 minute/unit ? 0 minute/hr) = RM 95,550 Hire worker = (5 worker) X (RM400) = RM 2,000 Lay off worker = (5 worker) X (RM600) = RM 3,000 Thus, total cost = RM 100,500 STRATEGY 2 Units Produced = (number of day per monthly) X (working days per pe daily) X (standard output per day) = (10 worker) X (26 day) X (60 minutes/hr ? 26 minutes/unit X 8hr) = 4800 units

MONTH| FORECAST DEMAND (UNIT)| UNIT PRODUCED| UNITEXCESS| UNIT SHORTAGE| OTUNITS| ENDINV| Jan| 5000 – 400 = 4600| 4800| 200| | | 200| Feb| 4900| 4800| | 100| 100| | Mar| 4500| 4800| 300| | | 300| Apr| 4200| 4800| 600| | | 600| May| 6300| 4800| | 1500| 1500| | Jun| 5000| 4800| | 200| 200| | Jul| 5100| 4800| | 300| | 300| Aug| 4800| 4800| | -| -| -| Sept| 4700| 4800| 100| | | 100| | | 43200| | | 1800| 1500| TOTAL PRODUCTION COST Regular Production Cost = (43200 units) X (26 days ? 8 hr) X (26 minute/unit ? 60 minute/hr) = RM 60,840 Overtime Cost (1800 unit) X (RM7. 50/hr) X (26 minute/unit ? 60 minute/hr) = RM 5,850 Inv. Holding Cost = (1500 unit) X (RM2. 40 per unit) = RM 3,600 Thus, total cost = RM 70,290 STRATEGY 3 Units Produced = (number of day per monthly) X (working days per pe daily) X (standard output per day) = (10 worker) X (26 day) X (60 minutes/hr ? 26 minutes/unit X 8hr) = 4800 units MONTH| FORECAST DEMAND (UNIT)| UNIT PRODUCED|

UNITEXCESS| UNIT SHORTAGE| OTUNITS| ENDINV| Jan| 5000 – 400 = 4600| 4800| 200| | | 200| Feb| 4900| 4800| | 100| | 100| Mar| 4500| 4800| 300| | | 300| Apr| 4200| 4800| 600| | | 600| May| 6300| 4800| | 1500| 900| | Jun| 5000| 4800| | 200| 200| | Jul| 5100| 4800| | 300| 300| | Aug| 4800| 4800| -| -| -| -| Sept| 4700| 4800| 100| | | 100| | | 43200| | | 1400| 1300| TOTAL PRODUCTION COST Regular Production Cost = (43200) X (RM5/hr) X (26 minute/unit ? 0 minute/hr) = RM 93,600 Overtime Cost = (1400 units) X (RM5/hr) X (26 minute/unit ? 60 minute/hr) = RM 3,033 Inv. Holding Cost = (1300 units) X (RM2. 40 per unit) = RM 3,120 Thus, total cost = RM 99, 753 STRATEGY 4 Units Produced = (number of day per monthly) X (working days per pe daily) X (standard output per day) = (10 worker) X (26 day) X (60 minutes/hr ? 26 minutes/unit X 8hr) = 4800 units

MONTH| FORECAST DEMAND (UNIT)| UNIT PRODUCED| UNITEXCESS| UNIT SHORTAGE| OTUNITS| ENDINV| Jan| 5000 – 400 = 4600| 4800| 200| | | 200| Feb| 4900| 4800| | 100| | 100| Mar| 4500| 4800| 300| | | 400| Apr| 4200| 4800| 600| | | 1000| May| 6300| 4800| | 1500| 1500| | Jun| 5000| 4800| | 200| 200| | Jul| 5100| 4800| | 300| 300| | Aug| 4800| 4800| -| -| -| -| Sept| 4700| 4800| 100| | | 100| | | 43200| | | 1000| 1800| TOTAL PRODUCTION COST Regular production cost = (43200) X (RM5/hr) X (26 minute/unit ? 0 minute/hr) = RM 93,600 Overtime Cost = (1000 units) X (RM7. 50/hr) X (26 minute/unit ? 60 minute/hr) = RM 3,250 Inv. Holding Cost = (1800 units) X (RM2. 40 per unit) = RM 4,320 Thus, total cost = RM 101,170 STRATEGY 5 Units Produced = (number of day per monthly) X (working days per pe daily) X (standard output per day) = (10 worker) X (26 day) X (60 minutes/hr ? 26 minutes/unit X 8hr) = 4800 units

MONTH| FORECAST DEMAND (UNIT)| UNIT PRODUCED| UNITEXCESS| UNIT SHORTAGE| OT UNITS(max=480Unit)| ENDINV| SUBUNIT| Jan| 5000 – 400 = 4600| 4800| 200| | | 200| | Feb| 4900| 4800| | 100| | 100| | Mar| 4500| 4800| 300| | | 400| | Apr| 4200| 4800| 600| | | 1000| | May| 6300| 4800| | 1500| 480| | 20| Jun| 5000| 4800| | 200| 200| | | Jul| 5100| 4800| | 300| 300| | | Aug| 4800| 4800| -| -| -| -| | Sept| 4700| 4800| 100| | | 100| | | | 43200| | | 980| 1800| 20| Overtime unit max = 4 X 2 X 26 per month ? 6 month/unit X 60 minute/unit = 480 units TOTAL PRODUCTION COST Regular Production Cost = (43200) X (RM5/hr) X (26 minute/unit ? 60 minute/hr) = RM 93,600 Overtime Cost = (980 units) X (RM7. 50/hr) X (26 minute/unit ? 60 minute/hr) = RM 3,185 Inv. Holding Cost = (1800 units) X (RM2. 40 per unit) = RM 4,320 Subcontracting Cost = (20 units) X (RM20 per unit) = RM 400 Thus, total cost = RM 101,505