《运营管理》课后习题答案

Chapter02-Competitiveness,Strategy,andProductivity

3.(1)(2)(3)(4)(5)(6)(7)

WorkerOverheadMaterialTotalMFP

WeekOutputCost@Cost@1.5Cost@$6Cost(2)+(6)

$12x40

130,0002,8804,3202,7009,9003.03

233,6003,3605,0402,82011,2202.99

332,2003,3605,0402J6011,1602.89

435,4003,8405,7602,88012,4802.84

*refertosolvedproblem#2

Multifactorproductivitydroppedsteadilyfromahighof3.03toabout2.84.

4.a.Before:80+5=16cartsperworkerperhour.

After:84+4=21cartsperworkerperhour.

b.Before:($10x5=$50)+$40=$90;hence80:$90=.89carts/$l.

After:($10x4=$40)+$50=$90;hence84.$90=.93carts/$1.

c.Laborproductivityincreasedby31.25%((21-16)/16).

Multifactorproductivityincreasedby4.5%((.93-,89)/.89).

*MachineProductivity

Before:80+40=2carts/$l.

After:84-r50=1.68carts/$l.

Productivityincreasedby-16%((1.68-2)/2)

Chapter03-ProductandServiceDesign

6.StepsforMakingCashWithdrawalfromanATM

1.InsertCard:MagneticStripShouldbeFacingDown

2.WatchScreenforInstructions

3.SelectTransactionOptions:

1)Deposit

2)Withdrawal

3)Transfer

4)Other

4.EnterInformation:

1)PINNumber

2)SelectaTransactionandAccount

3)EnterAmountofTransaction

5.Deposit/Withdrawal:

1)Deposit—placeinanenvelope(whichyou'llfindnearorintheATM)and

insertitintothedepositslot

2)Withdrawal一liftthe''WithdrawalDoor,“beingcarefultoremoveallcash

6.Removecardandreceipt(whichservesasthetransactionrecord)

Technical

RequirementsIngredientsHandlingPreparation

CustomerRequirements

TasteVV

AppearanceVVV

Texture/consistencyVV

Chapter04-StrategicCapacityPlanningforProductsandServices

czr•Actualoutputqcb

2.Efficiency=-----------------------=80%

Effectivecapacity

Actualoutput=.8(Effectivecapacity)

Effectivecapacity=.5(Designcapacity)

Actualoutput=(.5)(.8)(Effectivecapacity)

Actualoutput=(.4)(Designcapacity)

Actualoutput=8jobs

Utilization=.4

....Actualoutput

UTrtilization=-----；-----------；—

Designcapacity

、._Actualoutput8”.，

DesignCapacity=-----------------------=—=20jobs

Effectivecapacity.4

10.a.Given:10hrs.or600min.ofoperatingtimeperday.

250daysx600min.=150,000min.peryearoperatingtime.

Totalprocessingtimebymachine

ProductABc

148,00064,00032,000

248,00048,00036,000

330,00036,00024,000

460,00060,00030,000

Total186,000208,000122,000

186,000,.....

=----------=1.24-2machine

150,000

208,000,.....

NB=----------=1.38-2machine

150,000

122,000,..

Nc=----------=.81-1machine

150,000

Youwouldhavetobuytwo"A"machinesatatotalcostof$80,000,ortwo

"B"machinesatatotalcostof$60,000,orone"C”machineat$80,000.

b.Totalcostforeachtypeofmachine:

A(2):186,000min-60=3,100hrs.x$10=$31,000+$80,000=$111,000

B(2):208,0004-60=3,466.67hrs.x$11=$38,133+$60,000=$98,133

C(l):122,000-60=2,033.33hrs.x$12=$24,400+$80,000=$104,400

Buy2Bs-thesehavethelowesttotalcost.

Chapter05-ProcessSelectionandFacilityLayout

Desiredoutput=4

Operatingtime=56minutes

-eOperatingtime56minutesperhour一..

CT=---------------=-------------------------=14minutesperunit

Desiredoutput4unitsperhour

Task#ofFollowingtasksPositionalWeight

A423

B320

C218

D325

E218

F429

G324

H114

105

a.Firstrule:mostfollowers.Secondrule:largestpositionalweight.

AssemblyLineBalancingTable(CT=14)

Feasibletasks

WorkStationTaskTaskTimeTimeRemaining

Remaining

1F59A,D,G

A36B,G

G6——

IID77B,E

B25c

C41—

IIIE410H

H91—

IV159—

b.Firstrule:Largestpositionalweight.

AssemblyLineBalancingTable(CT=14)

Feasibletasks

WorkStationTaskTaskTimeTimeRemaining

Remaining

1F59A,D,G

D72一

IIG68A,E

A35B,E

B23—

IIIC410E

E46—

IVH951

15—

•Totaltime450八

Efficiency=------------------------=—=80.36%

CTxno.ofstations56

4.

2.MinimumCt=1.3minutes

TaskFollowingtasks

a4

b3

c3

d2

e3

f2

(T1

h0

WorkStationEligibleAssignTimeRemainingIdleTime

1aA1.1

b,c,e,(tie)B0.7

C0.4

E0.30.3

IIdD0.00.0

IIIf,gF0.5

G0.20.2

IVhH0.10.1

0.6

CTnX(idletime).6一〜

3.Idlepercent=---------------=--------=11.54percent

NxCT4(1.3)

4.Output=----=--------；——:———=323.1{roundsto323)copiers/day

CT1.3min./cycle

T-A/5Totaltime4.6__.

bL.1.Totaltime=4.6,CT=-------------=——=2.3minutes

N2

2.Assigna,b,c,d,andetostation1:2.3minutes[noidletime]

Assignf,g,andhtostation2:2.3minutes

OT420

3.Output=-----=-------=182.6copiers/day

CT2.3

4.

M­厂•“八420min./day小八•,,

MaximumCtis4.6.Output=--------；---------=91.30copiers/day

4.6min./cycle

Chapter06-WorkDesignandMeasurement

3.ElementPROTNTAFjgST

141.15.476

2.851.5051.2801.151.472

131.151.050

41.001.161.1601.151.334

Total4.332

8.A=24+10+14=48minutesper4hours

A嗡=2。

NT=6(.95)=5.70min.

ST=5.70x—?—

=7.125min.

1-.20

9.a.ElementPROTNTAST

091.151.505

551.151.098

31.05.56.5881.15.676

b.

x=.83

2

s=.034'zs2(.034)、

〜

n=，i01(.83)J=67.12observations

z=2.00

A=.01

2(.034)\

c.e=.01minutes=46.24,roundto47

.01J

Chapter07-LocationPlanningandAnalysis

1.FactorLocalbankSteelmillFoodwarehousePublicschool

1.Conveniencefor

customersHLM-HM-H

2.Attractivenessof

buildingHLMM-H

3.Nearnesstoraw

materialsLHLM

4.Largeamountsof

powerLHLL

5.PollutioncontrolsLHLL

6.Laborcostand

availabilityLMLL

7.Transportation

costsLM-HM-HM

8.Construction

costsMHMM-H

Location(a)Location(b)

4.FactorABCWeightABC

1.BusinessServices9552/918/910/910/9

2.CommunityServices7671/97/96/97/9

3.RealEstateCost3871/93/98/97/9

4.ConstructionCosts5652/910/912/910/9

5.CostofLiving4781/94/97/98/9

6.Taxes5551/95/95/94/9

7.Transportation6781/9_6/97/98/9

Total3944451.053/955/954/9

Eachfactorhasaweightof1/7.

394445

a.CompositeScores-.......—

BorCisthebestandAisleastdesirable.

b.BusinessServicesandConstructionCostsbothhaveaweightof2/9;theotherfactorseach

haveaweightof1/9.

5x+2x+2x=l=>x=1/9

ABC

c.CompositeScores---------------------

53/955/954/9

BisthebestfollowedbyCandthenA.

Xy

Location

5.

A37

B82

C46

D41

E64

Totals2520

ExjZ*

x=____25=5.0y=____20=4.0

n5n5

Hence,thecenterofgravityisat(5,4)andthereforetheoptimallocation.

Chapter08-ManagementofQuality

1.Checksheet

WorkTypeFrequency

LubeandOil12

Brakes7

Tires6

Battery4

Transmission1

Total30

Pareto

Lube&OilBrakesTiresBatteryTrans.

2

breaklunchbreak

Therunchartsseemstoshowapatternoferrorspossiblylinkedtobreaktimesortheendofthe

shift.Perhapsworkersarebecomingfatigued.Ifso,perhapstwo10minutebreaksinthemorning

andagainintheafternooninsteadofone20minutebreakcouldreducesomeerrors.Also,errors

areoccurringduringthelastfewminutesbeforenoonandtheendoftheshift,andthoseperiods

shouldalsobegivenmanagement'sattention.

4

OtherCord

Chapter9-QualityControl

SampleMeanRange

4.

179.482.6MeanChart:X±A2R=79.96±0.58(1.87)

280.142.3=79.96±1.08

380.141.2UCL=81.04,LCL=78.88

479.601.7

RangeChart:UCL=D4R=2.11(1.87)=3.95

580.022.0

LCL=D3R=0(1.87)=0

680.381.4[Bothchartssuggesttheprocessisincontrol:Neitherhasany

pointsoutsidethelimits.]

6.n=200ControlLimits=p±2、~~—

Vn

_=25，±2评笋

“-13(200)=.0096

=.0096±.0138

Thus,UCLis.0234andLCLbecomes0.

Sincen=200,thefractionrepresentedbyeachdatapointis

halftheamountshown.E.g.,1defective=.005,2defectives

=.01,etc.

Sample10istoolarge.

7.c==—=7.857Controllimits:c±3A/C二=7.857±8.409

14

UCLis16.266,LCLbecomes0.

Allvaluesarewithinthelimits.

14.LetUSL=UpperSpecificationLimit,LSL=LowerSpecificationLimit,

X=Processmean,o=Processstandarddeviation

ForprocessH:

X-LSL15-14.1-

-----------------------=93

3o⑶(.32).

USL-又16-15

=1.04

3G(3)(.32)

Cpk=min{.938,1.04}=.93

.93<1.0,notcapable

ForprocessK:

X-LSL33-30…

USL-4_36.5-33_117

3G-(3)(1).

Cpk=min{1.0J.17}=1.0

AssumingtheminimumacceptableC.is1.33,since1.0<1.33,theprocessisnot

capable.

ForprocessT:

X-LSL18.5-16.5.

----------=--------------=1.67

3o(3)(0.4)

USL-X20.1-18.5।”

-----------=--------------=1.33

3o(3)(04)

Cpk=min{1.67,1.33}=1.33

Since1.33=1.33,theprocessiscapable.

Chapter10-AggregatePlanningandMasterScheduling

7.a.Nobacklogsareallowed

PeriodMar.Anr.MavJun.JulyAug.Seo.Total

Forecast50445560504051350

Output

Regular40404040404040280

Overtime888883851

Subcontract2031220019

Output-Forecast04-4003-3

Inventory

Beginning0040003

Ending0400030

Average022001.51.57

Backlog00000000

Costs:

Regular3,2003,2003,2003,2003,2003,2003.20022,400

Overtime9609609609609603609606,120

Subcontract28004201,680280002,660

Inventory0202000151570

Total4.44()4.1804.6005.8404.4403.5754.17531.250

b.Levelstrategy

PeriodMar.ADF.MavJun.JulvAus.Seo.Total

Forecast50445560504051350

Output

Regular40404040404040280

Overtime888888856

Subcontract222222214

Output-Forecast06-5-10010-1

Inventory

Beginning0061001

Ending0610010

Average0.58

Backlog000990018

Costs:

Regular3.2003.2003,2003.2003,2003,2003.20022,400

Overtime9609609609609609609606,720

Subcontract2802802802802802802801,960

Inventory3035505580

Backlog180180360

Total4.4404.4704.4754.6254.6204.4454.44531.520

Period123456Total

Forecast160150160180170140960

Output

Regular150150150150160160920

Overtime1010010101050

Subcontract0010100020

Output-Forecast0100-1000

Inventory

Beginning00101000

Ending01010000

Average051050020

Backlog0000000

Costs:

Regular7,5007,5007,5007,5008,0008,00046,000

Overtime75075007507507503,750

Subcontract00800800001,600

Inventory20402080

Backlog000000

Total.825。8.2708.3409.0709.0508.75051,430

Chapter11-MRPandERP

F:2G:1H:1

J:2x2=4L:1x2=2A:1x4=4

D:2x4=8J:1x2=2D:1x2=2

Totals:F=2;G=1;H=1;J=6;D=10;L=2;A=4

b.

Stapler

TopAssemblyBaseAssembly

CoverSpringSlideAssemblyBaseStrikePadRubberPad2

SlideSpring

4.Beg.

MasterDay1234567

Inv.

Schedule

Quantity100150200

TableBeg.1234567

Inv

Grossrequirements100150200

Scheduledreceipts

Projectedonhand

Netrequirements100150200

Planned-orderreceipts100150200

Planned-orderreleases100150200

Beg.

WoodSections1234567

Inv.

Grossrequirements200300400

Scheduledreceipts100

Projectedonhand100100

Netrequirements100300400

Planned-orderreceipts100300400

Planned-orderreleases400400

BracesBeg.1234567

Inv

Grossrequirements300450600

Scheduledreceipts

Projectedonhand60606060

Netrequirements240450600

Planned-orderreceipts240450600

Planned-orderreleases240450600

Beg.

Legs1234567

Inv.

Grossrequirements400600800

Scheduledreceipts

Projectedonhand120120120120888871

Netrequirements280600800

Planned-orderreceipts308660880

Planned-orderreleases968880

10.Week1234

Material40806070

Week1234

Laborhr.160320240280

Mach.hr.120240180210

a.Capacityutilization

Week1234

Labor53.3%106.7%80%93.3%

Machine60%120%90%105%

b.Capacityutilizationexceeds100%forbothlaborandmachineinweek2,andfor

machinealoneinweek4.

Productioncouldbeshiftedtoearlierorlaterweeksinwhichcapacityis

underutilized.Shiftingtoanearlierweekwouldresultinaddedcarryingcosts;

shiftingtolaterweekswouldmeanbackordercosts.

Anotheroptionwouldbetoworkovertime.Laborcostwouldincreasedueto

overtimepremium,aprobabledecreaseinproductivity,andpossibleincreasein

accidents.

Chapter12-InventoryManagement

2.Thefollowingtablecontainsfiguresonthemonthlyvolumeandunitcostsfora

randomsampleof16itemsforalistof2,000inventoryitems.

Dollar

ItemUnitCostUsageUsageCategory

K34102002,000C

K352560015,000A

K36361505,400B

MIO1625400C

M2020801,600C

Z458025016,000A

F14203006,000B

F953080024,000A

F9920601,200C

D45105505,500B

D4812901,080C

D52151101,650C

D57401204,800B

N0830401,200C

P05165008,000B

P091030300C

a.Seetable.

b.Toallocatecontrolefforts.

c.Itmightbeimportantforsomereasonotherthandollarusage,suchascostofa

stockout,usagehighlycorrelatedtoanAitem,etc.

3.D=1,215bags/yr.

S=$10

H=$7