2021年面試技巧培訓資料

CaseQuestions

Casequestionsaremostcommonlyusedinconsultinginterviews，buttheycanbeusedinothersituations，suchasininterviewsformarketingpositionswithconsumergoodscompanies.Simplyput，acaseinterviewistheanalysisofabusinessquestion.Unlikemostotherinterviewquestions，itisaninteractiveprocess.Yourinterviewerwillpresentyouwithabusinessproblemandaskyouforyouropinion.Yourjobistoasktheinterviewerlogicalquestionsthatwillpermityoutomakeadetailedrecommendation.Themajorityofcaseinterviewersdon'thaveaspecificanswerthatyou，thecandidate，areexpectedtogive.Whattheinterviewerislookingforisathoughtprocessthatisatonceanalyticalandcreative.Here'sasamplecasequestion：

Youareadvisingacreditcardcompanythatwantstomarketaprepaidphonecardtoitscustomers.Isthisagoodidea?

You：Whatistheroleofourcompany?Dowesimplymarketthecardormustwecreatethemourselves?

Interviewer：Thiscardwillbeco-marketedwithanoutsidephonecompany.Wedon'tneedtoperformtelecommunicationsfunctions.

You：Whatareourexpensesconnectedwiththecard?

Interviewer：Wemustpay15centsforeveryminutewesell.Wealsohavetopay$1.00asastart-upcostforthecardandcardsystems.

You：Whatareourmarketingexpenses?

Interviewer：Wenormallyuseslipsofpaperthatareattachedtothebacksofourcreditcardpaymentenvelopes.Wesometimesalsosendcustomersadirectmailing-inaseparateenvelope.Orwecanhavetelemarketerscallselectedcustomers.

You：What'sthecostofeachofthesemarketingtechniques，andwhatistheirresponserate?

Interviewer：Telemarketershavea2percentresponserate，andcost$1.00percall.Directmailingscostus40centspermailingandhavea0.50percentrateofresponse.Ourpaymentattachmentshavea0.25rateofresponse，butonlycostus5centseach.

You：I'mgoingtoassumewewillsellone-hourphonecards.Thatwillcostus$9.00fortheminutesandadollarpercard-soeachcardcostsus$10.

Interviewer：Thatsoundsreasonable.

You：Andwhatisourexpectedrevenueonaone-hourphonecard?Whatisthecurrentmarketratefora60-minutephonecard?

Interviewer：Assumeit's50centsaminute.

You：Soifwesellthecardsfor$30，wehavea$20profit，minusourexpendituresonmarketing.

Interviewer：What'sourcoststructurelooklike?

You：Okay，let'sfigurethisout.Tosell1,000cardsthroughtelemarketing，wewouldneedtocontact50,000people.Thatwouldcostus$50,000.Tousedirectmail，wewouldhavetocontact200,000thousandpeople，which，at40centspermailing，costsus$80,000.Sincetheenvelopeinsertsaren'tveryreliable，wewillneedtocontact800,000peopleusingthatmethod.Butat5centseach，itcostsonly$20,000tosell1,000cards.

Wemake$20profitoneachcard.Butevenatthecheapestpromotionalvehicle，at$20profit，wewouldonlybreakeven，becauseourprofitson1,000cardswouldbe$20,000.Weshouldn'tmarketthiscard，unlesswecanfurthercutourmarketingcostsorincreasethepriceofthecard.Ifwecouldslicethecostoftheenvelopeattachmentsapennyorso，orsellthecardfor$35，orconvinceourco-marketertoreduceourcosts，itmightbeworthselling.

Commonly-askedQuestions

Companiesthesedayslookformorethanwhetheryou'reawittyorespeciallycoolindividualwhenitcomestopersonality.Amongthecharacteristicshighestontheirlistareteamworkandinnovation.Theymaynotaskwhetheryouareateamplayer，orcreative--doesn'tmeanyoushouldn'tgoaheadandtellthem.Butthenagain，alotofinterviewerswillaskyououtright：tellmewhyyourpersonaltraitswillworkhere.

1.Whyareyouapplyingforthisposition?

Probablythemostcommonlyaskedquestionatjobinterviews.Youneedtoconvinceyourinterviewerthatyouareenthusiasticaboutthejob.

2.Tellmeaboutatimewhenyouusedinitiative/Givemeanexampleofwhenyoucameupwithaninnovativesolution/Givemeanexampleofatimeyouexceededexpectations.

Inthisever-changingworldinwhichwework，employeesaresupposedtobeinnovative，tobeableto"thinkoutsideofthebox.Questionslikethese(suchasthewaythe"initiative"questionand"exceededexpectations"questionsareworded)canbeusedasopportunitiestotalkaboutcreativefaculties--pickaninstancewhenshowinginitiativemeantcomingupwithanout-of-the-ordinarysolution.

3.Iseeonyourresumethatyouservedaschairpersonofsuch-and-suchcommittee.Whatwasthatexperiencelike?

Alongwithinnovation，employersoftenlookforleadershipability.Ingeneral，interviewersarelookingforevidenceofawillingnesstolisten，anabilitytogivefeedback，andafirmnesswhenitcomestogettingthingsdone.

4.Whatwouldmembersofyourbasketballteam/businessschoolcohort/butterflycatchingexpeditionsayaboutyou?Tellusaboutatimeyouhadtodealwithadifficultteammember.

Teamworkisanotherhighlyvaluedtraitthesedays，companiesarelookingforemployeeswhoworkwellingroups.Ifyourinterviewerdoesn'tbringupteamwork，doityourself.Thesequestionsaresimilartotheleadershipquestions-interviewersarelookingforbothanopennesstoideasandawillingnesstonudgeteammemberstowardagoal.

5.Whydidyoudecidetoswitchcareers/Whydidyoudecidetogobacktoschool/Whydidyoutaketimeoffduringcollege?

Bepreparedtowalkthroughyourresumewithyourinterviewer，especiallyatcompaniesthatliketopromotefromwithin.Theywanttoknowthatyou'recommittedtotheindustryandwillbeloyaltotheircompany.

6.Wheredoyouseeyourselfin5years?

Youdon'tnecessarilyneedtosaythatyouwanttoworkforthecompanyforever，butyoushouldexpresshowyouthinkthepositiontowhichyouareapplyingwillhelpyougrow.

7.Soyoujustgraduated.Howdidyoulikeschool?

Lovedit.Learnedsomuch.AndletmetellyoualittlebitaboutwhattypesofactivitiesIwasinvolvedin.

8.Whatlessonsdidyoulearnfromyoulastjobthatyouthinkcanbetransferredtothisposition?

9.Whatdoyouconsideryourbiggestfault?

Interviewerslovethisquestion，eventhoughitsortofinvitesdishonesty.You'resupposedtosaysomethinglike："I'maperfectionist."Or："Itendtoworktoohard."Youmaywanttoprepareamorethoughtfulanswer，butyoushouldatleastanticipatethisquestion.

10.Ifyoucouldgoanywherefor24hours，withanunlimitedbudgetwherewouldyougo?

Sometimes，interviewerswillaskoff-the-wallquestionsjusttogetabettersenseofwhoyouareasaperson.

QuestionstoAskDuringYourSummerInternshipInterviews

*Canyougivemeanexampleofmysummerresponsibilities?Trytomakesuretheansweryoureceiveisasspecificaspossible.Particularlyifyou'renewtotheindustry，youwanttoensurethatyouwillperformworkthatisrepresentativeofafull-timeassociate.

*Howmanypeoplearetypicallygivenpermanentjoboffers?Andaskforpercentagestoo.Thisshowsyou'reinterestedinopportunitiesaftergraduationatthefirm，andallowsyoutoplanyourstrategicoptions.Somefirms，likeGoldmanSachs，areknownforgivingofferstoasmallproportionofthesummerclass.Youmaywanttotrybetteroddsatanotherfirm.

*WillIbeabletorotatebetweendepartments?Again，themoreyouknowaboutthecompany，thebetteryouwillbeabletodeterminewhichdepartmentinterestsyoumost，orwhetheryouwanttoworkatthefirmatall.Ifthere'saspecificdepartmentyouwanttoworkin，youshouldmakethisknown.

*Doyouprovideanyassistancewithrelocation?Manyfirmswillhelplocate，andevensubsidize，summerhousing.Ifthismakesadifferenceinwhetheryoutaketheposition，ask.

StrategiesforAnsweringBusinessCaseQuestions

Ifyou'regoingintoaninterviewwhereyoumightexpectacasequestion(abusinessquestionpresentedtoyouforyourdetailedanalysis)，it'simportanttohaveafewbasictipsdownpat.

1.Takenotes.

Asyourinterviewerpresentsyourcase，besuretotakecarefulnotesonthenumbersorotherfactsgiven.(Alwaysbringanotepadandapentoaconsultinginterview.)Youdon'twanttoaskyourinterviewertolaterrepeatinformationthathasalreadybeengiven.

2.Askquestions.

Yourinterviewerexpectsyoutoaskquestions--asmanyintelligentquestionsasyouneedtoobtainanaccuratepictureoftherelevantfactsinthecase.Manyinexperiencedcaseintervieweesmaketheerrorofnotaskingtheirintervieweranyquestions，perhapsafraidthattheywilllookignorant，ornotwishingto"bother"theinterviewer.Onthecontrary--notaskingquestionsisafatalerrorinacaseinterview.Ifyoudon'tknowthefirstthingaboutthehelicoptermarket，askhowmuchitcoststomanufacturearotor.Ifyouneedtoestimatethedemandforabeef-flavoredpotatosnackinWichita，Kansas，thenfeelfreetoaskthepopulationofWichitaandenvirons.

3.Bepreparedtotakecharge.

Youwilloftenfindthatyourinterviewerwilldirectyourlineofquestioningtoaspecificarea，butyoumustalwaysbereadytocontroltheconversationincasetheinterviewerdoesnotdirectyourreasoning.Ifyouareunsure，simplyasktheinterviewer.Forinstance，ifyoufindtheinterviewerofferinglittledirectionasyoumovethroughyourinitialscoopingquestions，youmaywishtoask，"Ifindthelackofariskassessmenttobeapotentialshowstopper.MightIasksomedetailedquestionsaboutthis?"Oryoumightsay，"Givenwhatyouhavetoldmeaboutthesituation，Iwouldliketodrilldownforfurtherclarityregardingtheclient'scurrentrelationshipwithitsdistributionpartner.WouldthatbeOK?"Inthisway，youtakechargeofthelineofquestioningwithoutsteppingontheinterviewer'srole.

4.Makenoassumptions！

Asacaseinterviewee，youshouldnevermakeanyassumptions.Youshouldassumethepersonaofanactualconsultanttryingtolearnaboutanassignment.Itmightseemobviousthatthereisnopreexistingworkplan(becauseiftherewas，whywouldthisbeacaseinterview?)butyoushouldask.Youshouldalsoaskifthecompanyhasencounteredasimilarproblem，orwhatothercompaniesinthefieldhavedonewhenfacedbysimilarproblems.Yourinterviewermaynotreleasethatinformationbutwillbeimpressedthatyouaskedthesesensiblequestions.Somegoodbasic"professional"questionstoask，whichapplytomostcases：

Whohiredus?

Howlongwilltheseengagementslast?

Isthereaworkplan?

Hasthecompanyfacedthisproblem(oropportunity)before?

Ifso，howdiditreact?

Whatwastheoutcome?

Whathaveothercompaniesfacingthissituationdone?

Hasthefirmalreadydoneanyresearchintotheissue?

Ifso，whatwereitsfindings?

5.Maintaineyecontact.

Alwaysmaintaindirecteyecontactduringthecaseinterview.Eyecontactiscriticalwhenansweringcasequestions--itdemonstratesconfidenceandauthority.Rememberthatinconsultingyoumayfindyourselfinfrontof20executivesatamajorcorporationpresentingastrategyyouwerebriefedononlyahalf-hourago.Andthenyouhavetoanswerquestions！Soyoucanseewhybusinesscaseinterviewingissoimportanttoconsulting--itisadirectparalleltotheenvironmentconsultantsmustfaceeveryday.

FinanceInterviewQuestions

WithWallStreetsalariesskyrocketing，investment-bankingjobsareashotasever.Thismeansit'sespeciallyimportanttobepreparedforbankingandfinanceinterviews.Thesefinanceinterviewquestionsshouldhelp.Formorequestionsandinterviewadvice，readtheVGuidetoFinanceInterviews.

1.Howwouldyouvalueacompanyyou'reconsideringbuying?

OneofthemostcommonquestionsWallStreetinterviewersask.(Othervariationsofthisquestionare："howwouldyouvalueastockyouwereconsideringbuying，takingpublic，etc.)WallStreetersusethisquestiontoseparatethefinancejocksfromtheneophytes.Here'sabasicanswerthatshouldimpressyourinterviewer：

Oneanswertothisquestionistodiscountthecompany'sprojectedcashflowsbya"risk-adjusteddiscountrate."Afterprojectingthefirstfiveor10years，youaddina"TerminalValue,"whichrepresentsthepresentvalueofallthefuturecashflowsthataretoofarintothefuturetoproject.YoucancalculatetheTerminalValueinoneoftwoways：(1)youtaketheearningsofthelastyearyouprojected，sayyear10，andmultiplyitbysomemarketmultiplelike20timesearnings，andthat'stheterminalvalue；or(2)youtakethelastyear，sayyear10，andassumesomeconstantgrowthrateafterthat，perhaps10%.Thepresentvalueofthisgrowingstreamofpaymentsafteryear10istheTerminalValue.

Note：Tofigureoutwhat"discountrate"youwouldusetodiscountthecompany'scashflows，tellyourintervieweryouwouldusethe"CapitalAssetPricingModel"(or"CAP-M").(Inanutshell，CAPMsaysthattheproperdiscountratetouseistherisk-freeinterestrateadjustedupwardstoreflectthisparticularcompany'smarketriskor"beta.")

Finally，youshouldalsomentionothermethodsofvaluingacompany，includinglookingat"comparables,"-thatis，howothersimilarcompanieswerevaluedrecentlyasamultipleoftheirsales，netincome，orsomeothermeasure.

2.WalkmethroughthemajorlineitemsonaCashFlowstatement.

Aquestiontotestyouraccountingskills.Theanswer：FirsttheBeginningCashBalance，thenCashfromOperations，thenCashfromInvestingActivities，thenCashfromFinancingActivities，andfinallytheEndingCashBalance.

3.WhatisEBITDA?Alsoknownas"cashflow,"EBITDAisEarningsBeforeInterest，Taxes，Depreciation，andAmortization.

4.Sayyouknewacompany'snetincome.Howwouldyoufigureoutits"cashflow"?

Abasicanswer：Youstartwiththecompany'snetincome.Thenyouaddbackdepreciationandamortization.Thenyousubtractthecompany'sCapitalExpenditures(called"CapEx"forshort，thisishowmuchmoneythecompanymustinvesteachyearonplantsandequipment).Thenumberyougetisthecompany'scashflow：

5.CompanyAisconsideringacquiringCompanyB.CompanyA'sP/Eratiois55timesearnings，whereasCompanyB'sP/Eratiois30timesearnings.AfterCompanyAacquiresCompanyB，willCompanyA'searningspersharerise，fall，orstaythesame?

CompanyA'searnings-per-sharewillrise，becauseofthefollowingrule：whenahigherP/EcompanybuysalowerP/Ecompany，theacquirer'searnings-per-sharewillrise.Thedealissaidtobe"accretive,"asopposedto"dilutive,"totheacquirer'searnings.

Defeatingthe12-BallQuestion

Someinterviewquestionsarenotoriouslydifficult.Thisparticularlogicproblemhasmadeitsappearanceatvariousconsulting，investmentbankingandtechfirms(includingMcKinseyandMicrosoft).Willyoubepreparedifyourinterviewerspringsuponyoutheknotty"12ball"dilemma?ThankstoVaultReports，youcananswerinsafety！

Here'sthequestion：

Youhave12balls.Allofthemareidenticalexceptone，whichiseitherheavierorlighterthantherest-itiseitherhollowswhiletherestaresolid，orsolidwhiletherestarehollow.Youhaveasimpletwo-armedscale，andarepermittedthreeweightings.Canyouidentifytheoddball，anddeterminewhetheritisholloworsolid?

Thislogicproblemissuretoputyouranalyticalabilityondisplay！First，we'llexaminewhatthoughtprocessesaninterviewerislookingfor，andthenwe'lldiscussonesolution.

Startwiththesimplestofobservations.Thenumberofballsyouweighagainsteachothermustbeequal.Yeah，it'sobvious，butwhy?Becauseifyouweigh，saythreeballsagainstfive，youarenotreceivinganyinformation.Inaproblemlikethis，youaretryingtoreceiveasmuchinformationaspossiblewitheachweighing.

Forexample，oneofthefirstmistakespeoplemakewhenexaminingthisproblemisthattheybelievethefirstweighingshouldinvolvealloftheballs(6against6).Thisweighinginvolvesalloftheballs，butwhattypeofinformationdoesthisgiveyou?Itactuallygivesyounonewinformation.Youalreadyknowthatoneofthesideswillbeheavier，andbyweighing6against6，youwillsimplyconfirmthisknowledge.Still，youwanttogaininformationaboutasmanyballsaspossible(soweighing1against1isobviouslynotagoodidea).Thusthebestfirstweighingis4against4.Thatway，youreserve4balls，andcanobtainsomeinformationabouteachsubsetof4.

Secondly，ifyouthinkthroughthisproblemlongenough，youwillrealizehowprecioustheinformationgainedfromaweighingis：Youneedtotransfervirtuallyeverypieceofinformationyouhavegainedfromoneweighingtothenext.Sayyouweigh4against4，andthescalebalances.Luckyyou！Nowyouknowthattheoddballisoneoftheunweighed4.Butdon'tgiveintotheimpulsetosimplyworkwiththoseballs.Inthisweighing，you'vealsolearnedthattheeightballsonthescalearenormal.Trytousethisinformation.

Youmustbebothcreativeandanalytical.Mostpeoplewhoworkthroughthisproblemconsideronlyweighinganumberofballsagainsteachother，andthentakinganothersetandweighingthem，etc.Thiswon'tdo.Thereareanumberofothertypesofmovesyoucanmake-youcanrotatetheballs，fromonescaletoanother，youcanswitchtheballs，etc.

Let'slookatonesolution.

Forsimplicity'ssake，wewillrefertoonesideofthescaleasSideA，andtheotherasSideB.

Step1：Weigh4ballsagainst4others

CaseA：If，onthefirstweighing，theballsbalance

Iftheballsinourfirstweighingbalanceweknowtheoddballisoneofthosenotweighed，butwedon'tknowwhetheritisheavyorlight.Howcanwegainthisinformationeasily?Wecanweighthemagainsttheballsweknowtobenormal.So：

Step2：PutthreeoftheunweighedballsontheSideA；putthreeballsthatareknowntobenormalonSideB.

I.Ifonthissecondweighing，thescalebalancesagain，weknowthatthefinalunweighedballistheoddone.

a.Step3.Weighthefinalunweighedball(theoddone)againstoneofthenormalballs.Withthisweighing，wedeterminewhethertheoddballisheavyorlight

II.If，ontheotherhand，withthissecondweighing，thescaletipstoSideA，weknowthattheoddballisheavy.(IfittipstoSideB，weknowtheoddballislight，butlet'sproceedwiththeass

BrandManagementCaseQuestion：TheBrandLaunch

WhileWallStreetmaycontrolourpursestrings，andHollywoodmaycontrolourdreamsandimaginations，itisthe"brandmanagers"whoseguidinghandsshapeeverythingweeatandwear，andinfact，shapethewaywethinkaboutthesethings.Themostsought-afterbrandmanagementpositionsarewithleadingconsumerproductscompaniessuchasProcter&GambleandGeneralMills.Toclimbtosuchloftyheights，brandmanagers(sometimesknownas"marketingmanagers")undergorigorousinterviewsthatofteninvolvecasequestions.Brandcasesvaryinbreadthandspecificity-somemaybeaboutpromotions，someaboutpricing，othersaboutlong-termstrategy.Vtakesalookatonetypeofbrandcase：the"BrandLaunch."

SAMPLEQUESTION：Ifourcompanywerelookingtointroduceacarpetcleanertoourlineofproducts，howwouldyougoaboutdevelopingabusinessplan?

Ingeneral，interviewersareinterestedinwhatkindsofquestionsyouask，andyourunderstandingofmarketforces.Here，theinterviewerislookingforananswerthatdescribesthe"process"youwoulduseindevelopingabusinessplan，notaskingforabusinessplanitself.Theinterviewermaybepleasantlysurprisedifyouhappentoknowthesizeofthecarpetcleanermarket-buttheycertainlydon'texpectit.Here'soneapproachtoattackingthiscase：

STEP1：ANALYZETHEMARKET：Thefirstthingthemarketingmanagershoulddoisgatherallavailableinformationaboutthemarket.Thelogicalplacetostartwouldbethecarpetcleanermarketanditsfuture.Howlargeisthecarpetcleanermarketcurrently?Isitexpectedtogrowinthenextseveralyears?Whatarethemaincompaniesinvolved?Finally，howofteniscarpetcleanersold，andinwhat"channels"-ingrocerystores，inhardwarestores，inconveniencestores，asanimpulsebuy，asanemergencybuy，etc?

STEP2：ASSESSYOURCOMPANY'SSTRENGTHSANDWEAKNESSES：Thenextissuesamarketershouldbeawareofarehisorhercompany'sstrengthsandweaknesseswhenitcomestothismarket.Doesthecompanyproducesimilarproducts，andthereforehaveabaseofR&Dexpertise?Doesthecompanyhaveadistributionnetworkinplace?Isthecompanysittingonextracapitalitislookingtoinvestintoaproductlaunch?Makesuretoidentifythecompany'sweaknessesaswell.Perhapsthecompanyisbestknownamonghomeownersforitseasytouseanddisposablecleaningproducts-thisdemographicgroupmaynotoverlapmuchwiththemarketforcarpetcleaner.

STEP3：ASSESSCONSUMERPREFERENCES：Adiligentbrandwillalsoconsiderbroaderissuesindevelopingabusinessplan.Onemajorcategoryoftheseisconsumerpreferences.Arehomeownersoptingforhardwoodfloorsandthrowdownrugsratherthancarpeting?

STEP4：CONSIDERMACROTRENDSandOTHERISSUES：Anothermajorconcernformarketersismajormacrotrends，suchasdemographictrends.Whatisthekeydemographicgroupthatusesthisproduct?Isthisgroupbecominglargerovertime，orshrinking?Areforeignmarketsbeginningtoconsumemorecarpetcleaner?Legalandregulatoryissuesshouldalsobeconsidered.Areaerosolcarpetcleanersbecominglessfeasiblebecauseofenvironmentalregulations?

STEP5：DETERMINEOURCOMPANY'SOBJECTIVES：Finally，youmustdetermineyourcompany'sobjectives.Becauseconsumertrendsarefickle，andtechnologicalinnovationcanquicklytransformanindustry，brandstrategyshouldingeneralnotbetoofar-sighted.Afive-yearplanisagood，safewaytocompromisetheneedforlong-termstrategywiththepitfallspredictingfuturestrategyinevitablybrings.

Interviewersmaypresentyouwithobjectivesatthestartofthecase.Iftheydon't，ask.Ifnoobjectivesareproffered，funnelyourthinkingintothreemainareas：marketsharegrowth，financialperformance，andbrandidentity.

Guesstimates

Guesstimatesarecommonlyaskedinconsultingandinvestmentbankinginterviews.Generally，yourinterviewerasksyoutoestimatethenumberorsizeofsomething，andobservesyourreasoningprocess.Mostinterviewersdon'tcareifyouactuallygetthecorrectnumber-whattheywanttoseeisthatyouareabletologicallythinkthroughaprocess，creativelythinkthroughanypossibleexceptionsorshortcuts，andcalculatebasicsumsinyourhead.Youwon'tbegivenanyrealdata(thoughyouwon'tneedtoknowmuchmorebeyondthefactthattheUnitedStateshasabout270millioninhabitantsand25millionbusinesses)，andyoushouldn'trequestany；it'sirrelevanttotheproblemathand.Makereasonableassumptions，witheasy-to-work-withnumbers，andgofromthere(rememberthatyou'reexpectedtouseapenandnotepadtoworkthroughyourcalculations).

Theseguesstimatesmayalsoinvolveelementsofcreativityandproblemsolving.Forexample，whenposedthequestion"Howmuchchangewouldyoufindonthefloorofamall?"youmightwanttoask"Isthereafountaininthemall?"Let'stakealookatasampleguesstimate：

1.HowmanygallonsofwhitehousepaintaresoldintheU.S.eachyear?

THE"STARTBIG"APPROACH：Ifyou'renotsurewheretobegin，startwiththebasicassumptionthatthereare270millionpeopleintheU.S.(or25millionbusinesses，dependingonthequestion).Ifthereare270millionpeopleintheUnitedStates，perhapshalfofthemliveinhouses(or135millionpeople).Theaveragefamilysizeisabout3，sotherewouldbe45millionhousesintheUnitedStates.Let'saddanother10percenttothatforsecondhousesandhousesusedforotherpurposesbesidesresidential.Sothereareabout50millionhouses.

Ifhousesarepaintedevery10yearsonaverage(noticehowwedeftlymakethatnumbereasytoworkwith)，thenthereare5millionhousespaintedeveryyear.Assumingthatonegallonofpaintcovers100squarefeetofwall，andthattheaveragehousehassquarefeetofwalltocover，theneachhouseneeds20gallonsofpaint.So100milliongallonsofpaintaresoldperyear(5millionhousesx20gallons).(Note：Ifyouwanttobefancy，youcanaskyourinterviewerwhetheryoushouldincludeinnerwallsaswell!)If80percentofallhousesarewhite，then80milliongallonsofwhitehousepaintaresoldeachyear.(Don'tforgetthatlaststep!)

THE"STARTSMALL"APPROACH：Youcouldalsostartsmall，andtakeatownof27,000(aboutonetenthousandthofthepopulation).Ifyouusethesameassumptionthathalfthetownlivesinhousesingroupsofthree，thenthereare4,500houses，plusanother10percent，thentherearereally5,000housestoworryabout.Paintedevery10years，500housesarebeingpaintedinanygivenyear.Ifeachhousehas2,000squarefeetofwall，andeachgallonofpaintcovers100squarefeet，theneachhouseneeds20gallons-andso10,000gallonsofhousepaintaresoldeachyearinyourtypicaltown.Perhaps8,000ofthosearewhite.Multiplyby10,000-youhave80milliongallons.

Yourinterviewermaythenaskyouhowyouwouldactuallygetthatnumber，onthejob，ifnecessary.Useyourcreativity-contactingmajorpaintproducerswouldbesmart，puttinginacalltoHUD'sstatisticsarmcouldhelp，orevenconductingasmallsampleofthesecondcalculationinafewrepresentativetownsispossible.

Otherguesstimates：

HowmuchorangejuiceisconsumedeachdayinAmerica?

Howmanygolfballswouldfitintoa747?

HowmanygrocerystoresarethereintheU.S.?

Brainteasers

High-techcompanies，investmentbanksandconsultingfirmsarefamousfortheirbrainteasers.Anyone，afterall，cancomeupwithacannedanswertodisplaytheirleadershipandmanagementskills-butfewerpeoplecanquicklycomeupwiththreesolidreasonswhyamanholecoverisround.Whetheryou'reapplyingforatechnical，corporatefinanceormarketingposition，expecttogetafewofthesebeauties.Creativityandmentalflexibilityandspeedareofparamountimportancetohigh-techfirms，andonesurefirewaytotestthesequalitiesisthroughtheseslightlyoffbeatquestions.

Ifyoufieldoneofthesebrainteasers，yourinterviewermaygiveyouatimelimit.Don'tbecomeflustered.Simplytrytothinkthroughthequestionfromeveryangleyoucan.Mostquestionsrequireeitherlogic，thatever-popular"outofthebox"thinking，orboth.

1.Ifyoulookataclockandthetimeis3:15，whatistheanglebetweenthehourandtheminutehands?

Theanswertothisisnotzero！Thehourhand，remember，moves