ananimalscount,Hi?

　　Mycatcan.

　　Howdoyouknow,Hi?

　　Iasked"Whatis6minus6"anditsaidnothing.

　　Numbers:everyone'slanguage.

　　aHowmanylanguagesdoyouknow?

　　Everyoneknowsatleasttwo--hisorherownlanguageandtheinternationallanguageofnumbers.

　　Ancientnumbers

　　Inancienttimes,peoplewrotenumbersinmanydifferentways.

　　However,theynearlyallcountedintens.

　　Zero

　　Thesystemofnumberstodayconsistsofthenumbersfrom1to9and0(zero).

　　TheIndiansfirstinventedanddevelopedthe1to9systemofnumbers.

　　Theytheninventedthezero.

　　Theinventionofzerohelpedpeoplewritebignumbersandcalculatemoreeasily.

　　Whitthesetennumbers,wecanwriteanynumberfromthebiggesttothesmallest.

　　Calculatingmachines

　　Oneofthefirstcalculatingmachineswastheabacus.

　　Abacusesarefastandaccurate.

　　Ontheabacus,thebeadsonthewiresrepresentones,tens,hundredsandthousands,startingfromthebottomwire.

　　Theabacusinthepictureshowsanumber.

　　Writeitdowninfigures,andtheninwords.

　　Multiplyitbyzeroandthenadd1.Whatistheanswer?

　　Modernelectroniccalculatorscanadd,subtract,multiplyanddivide.

　　Theycanalsocalculatepercentagesandsquareroots.

　　Computersareverypowerfulcalculatingmachines.

　　Acomputercandomillionsofcalculationsinaflash.

　　Cardinalandordinalnumbers

　　3three5five6six9nine

　　13thirteen15fifteen16sixteen19nineteen

　　30thirty50fifty60sixty90ninety

　　32thirty-two54fifty-four67sixty-seven98ninety-eight

　　100onehundred200twohundred375threehundredandseventy-five1,000onethousand

　　4,189fourthousandonehundredandeighty-nine

　　15,362fifteenthousandthreehundredandsixty-two

　　100,000onehundredthousand

　　284,653twohundredandeighty-fourthousandsixhundredandfifty-three

　　1,000,000onemillion

　　5,367,982fivemillionthreehundredandsixty-seventhousandninehundredandeighty-two

　　Weuseordinalnumbertoshowtheorderofthings.

　　Weformmostordinalsbyadding-thtothecardinalnumbers.

　　Therearealsoexceptions,likefirst,secondandthird.

　　1stfirst2ndsecond3rdthird5thfifth

　　8theighth9thninth12thtwelfth13ththirteenth

　　20thtwentieth21sttwenty-first22ndtwenty-second23thtwenty-second100thhundredth

　　t10

　　0Mayiscallingherfriend,Rita.Readtheirconversationandpractiseit.

　　ThenworkinpairstochecktheotherhomeworkproblemsinMay'snotebook.

　　RITA:28906521(twoeightninezero,sixfivetwoone).

　　MAY:Hello,Rita.ThisisMay.

　　RITA:Hi,May.WhatcanIdoforyou?

　　MAY:Imadeamistakewithmyhomework,Ithink.CanIcheckitwithyou?

　　RITA:Sure.Whichone?

　　MAY:Number5.Isit0.92(zeropointninetwo)times18.18(eighteenpointoneeight)?

　　RITA:No,itshouldbe0.92times18.16(eighteenpointonesix).

　　MAY:Thanks,Rita.Seeyoutomorrow.Bye.

　　RITA:Goodbye,May.

　　Trafficaccidents

　　LiJieaskedOfficerChe