美國數(shù)學(xué)競賽AMC8講座課件

AMC8

專題講座AMC8專題講座1①①測(cè)試中心：TianjinTestCenter（Grade8）②姓名：LASTNAME為姓，F(xiàn)IRSTNAME為名姓名為4個(gè)字的同學(xué)，兩邊各寫兩個(gè)方框中一律左對(duì)齊，并在下方相應(yīng)位置填涂③性別：Female女Male男④不填涂⑤年級(jí)：按照實(shí)際情況填涂⑥年齡：按照實(shí)際情況填涂⑦考生簽字：中文姓名⑧不填涂⑨答題區(qū)域：每道題只有一個(gè)答案是正確的，將自己所選擇的答案的序號(hào)涂黑一律使用2B鉛筆任何填涂的位置必須完全覆蓋整個(gè)圓圈②③④⑤⑥⑦⑧⑨①①測(cè)試中心：②③④⑤⑥⑦⑧⑨2詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位3數(shù)number數(shù)字digit

個(gè)位unit

個(gè)位數(shù)字unitsdigit

十位數(shù)字tensdigit

百位數(shù)字hundredsdigit

千位數(shù)字thousandsdigit

三位數(shù)three-digitnumber詞匯篇——

數(shù)與數(shù)位1數(shù)number詞匯篇——數(shù)與數(shù)4實(shí)數(shù)realnumber

有理數(shù)rationalnumber

整數(shù)integer/wholenumber

正整數(shù)positiveinteger負(fù)整數(shù)negativeinteger自然數(shù)naturalnumber

奇數(shù)oddnumber/integer偶數(shù)evennumber/integer

因數(shù)factor/divisor公因數(shù)commonfactor/divisor質(zhì)因數(shù)primefactor/divisor

倍數(shù)multiple（最?。┕稊?shù)(least)commonmultiple

質(zhì)數(shù)primenumber合數(shù)compositenumber

分?jǐn)?shù)fraction

分子numerator分母denominator最簡分?jǐn)?shù)simplefraction

真分?jǐn)?shù)properfraction假分?jǐn)?shù)improperfraction帶分?jǐn)?shù)mixedfraction

繁分?jǐn)?shù)complexfraction

小數(shù)decimal

純小數(shù)decimalfraction無限小數(shù)infinitedecimal循環(huán)小數(shù)recurringdecimal

無理數(shù)irrationalnumber正數(shù)positivenumber負(fù)數(shù)negativenumber詞匯篇——

數(shù)與數(shù)位2實(shí)數(shù)realnumber詞匯篇——數(shù)與數(shù)位25值value絕對(duì)值absolutevalue倒數(shù)reciprocal/inverse平均值mean/average

加權(quán)平均數(shù)weightedaverage幾何平均數(shù)geometricaverage中位數(shù)median眾數(shù)mode平方數(shù)squarenumber

底數(shù)base冪exponent數(shù)列sequence

序數(shù)ordinal最大數(shù)maximum最小數(shù)minimum

等差（等比）數(shù)列arithmetic(geometric)sequence

連續(xù)的consecutive連續(xù)整數(shù)consecutiveinteger循環(huán)cycle詞匯篇——

數(shù)與數(shù)位3值value絕對(duì)值absolute6詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位7加add/plus和sum/total減subtract差difference乘multiply/times積product

乘方power階乘factorial除divide商quotientdividend÷divisor=quotient

divisible平方square平方根squareroot······remainder立方cube立方根cuberoot比例proportion比ratio公比commonratio詞匯篇——

運(yùn)算1加add/plus8增加increase

增加了increaseby增加到increaseto減少decrease/reduce

減少了decreaseby減少到decreaseto比較關(guān)系等于equal

不同distinct

估計(jì)estimation

近似approximate

大于morethan不大于nomorethan小于lessthan

四舍五入roundto詞匯篇——

運(yùn)算2增加increase詞匯篇——運(yùn)算29詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位10直線line/straightline端點(diǎn)endpoint線段segment中點(diǎn)midpoint平分bisect對(duì)稱symmetry相交intersect平行parallel平行線parallellines詞匯篇——

幾何圖形1直線line/straightline11平面plane陰影部分shadedregion詞匯篇——

幾何圖形2平面plane詞匯篇——幾何圖形212對(duì)角線diagonal周長perimeter/circumference面積area詞匯篇——

幾何圖形3詞匯篇——幾何圖形313正方形square

邊長side長方形（矩形）rectangle菱形rhombus梯形trapezoid等邊形equilateral多邊形polygon

正多邊形regularpolygon詞匯篇——

幾何圖形4詞匯篇——幾何圖形414角angle

銳角acuteangle直角rightangle鈍角obtuseangle平角straightangle周角roundangle詞匯篇——

幾何圖形5詞匯篇——幾何圖形515角angle

夾角includedangle角平分線anglebisector度degree分minute秒second詞匯篇——

幾何圖形6詞匯篇——幾何圖形616三角形triangle

頂點(diǎn)vertex（復(fù)數(shù)vertices）對(duì)邊oppositeside底邊base高h(yuǎn)eight/altitude內(nèi)角interiorangle外角exteriorangle中位線medianofatriangle詞匯篇——

幾何圖形7詞匯篇——幾何圖形717三角形triangle

等邊三角形equilateraltriangle

正三角形regulartriangle等腰三角形isoscelestriangle不等邊三角形scalenetriangle詞匯篇——

幾何圖形8詞匯篇——幾何圖形818三角形triangle

直角三角形righttriangle斜三角形obliquetriangle銳角三角形acuteangledtriangle鈍角三角形obtuseangledtriangle

詞匯篇——

幾何圖形9詞匯篇——幾何圖形919直角三角形

垂直perpendicular直角邊leg斜邊hypotenuse勾股定理Pythagoreanproposition詞匯篇——

幾何圖形10詞匯篇——幾何圖形1020圓circle/round

圓心centerofacircle直徑diameter半徑radius切線tangent詞匯篇——

幾何圖形11詞匯篇——幾何圖形1121

半圓semicircle扇形sector圓心角centralangle詞匯篇——

幾何圖形12詞匯篇——幾何22立體solid

表面積surfacearea體積volume

橫截面crosssection深度depth正多面體regularsolid/polyhedron長方體rectangularsolid圓柱體cylinder/circularcylinder圓錐cone球體sphere

詞匯篇——

幾何圖形13立體solid詞匯篇——幾何圖形1323詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位24

米meter千米kilometer

分米decimeter厘米centimeter

毫米millimeter微米micron

碼yard英尺foot英寸inch

克gram千克kilogram

加侖gallon夸脫quart品脫pint詞匯篇——

單位名稱米meter25詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位26美元dollar美分cent1美分硬幣penny5美分硬幣nickel10美分硬幣dime25美分硬幣quarter價(jià)格price

成本價(jià)costprice

標(biāo)價(jià)listprice零售價(jià)retailprice

利潤profit利息interest詞匯篇——

商業(yè)詞匯美元dollar27方法篇Breakdown：化長為短，逐個(gè)擊破Keywords：尋找關(guān)鍵詞Son/Mother：圖文結(jié)合Miss/Pick：丟掉無用信息，留住有用信息方法篇Breakdown：化長為短，逐個(gè)擊破28Ms.Osborneaskseachstudentinherclasstodrawarectanglewithintegersidelengthsandaperimeterof50units.Allofherstudentscalculatetheareaoftherectangletheydraw.Whatisthedifferencebetweenthelargestandsmallestpossibleareasoftherectangles?(A)76(B)120(C)128(D)132(E)136

方法篇——BreakdownMs.Osborneaskseachst29方法篇——BreakdownChandlerwantstobuya$500mountainbike.Forhisbirthday,hisgrandparentssendhim$50,hisauntsendshim$35andhiscousingiveshim$15.Heearns$16perweekforhispaperroute.Hewilluseallofhisbirthdaymoneyandallofthemoneyheearnsfromhispaperroute.Inhowmanyweekswillhebeabletobuythemountainbike?(A)24(B)25(C)26(D)27(E)28方法篇——BreakdownChandlerw30方法篇——Breakdown

Picktwoconsecutivepositiveintegerswhosesumislessthan100.Squarebothofthoseintegersandthenfindthedifferenceofthesquares.Whichofthefollowingcouldbethedifference?(A)2(B)64(C)79(D)96(E)131方法篇——BreakdownPicktwoc31方法篇——BreakdownEverydayatschool,Joclimbsaflightof6stairs.Jocantakestairs1,2,or3atatime.Forexample,Jocouldclimb3,then1,then2stairs.InhowmanywayscanJoclimbthestairs?(A)13(B)18(C)20(D)22(E)24方法篇——BreakdownEveryday32方法篇Breakdown：化長為短，逐個(gè)擊破Keywords：尋找關(guān)鍵詞Son/Mother：圖文結(jié)合Miss/Pick：丟掉無用信息，留住有用信息方法篇Breakdown：化長為短，逐個(gè)擊破33方法篇——KeywordsThesmallestpossibleaverageoffourdistinctpositiveevenintegersis______.方法篇——KeywordsThesmalles34Mindymadethreepurchasesfor$1.98,$5.04and$9.89.Whatwashertotal,tothenearestdollar?(A)$10(B)$15(C)$16(D)$17(E)$18

方法篇——KeywordsMindymadethreepurchas35方法篇——Keywords

Apositivewholenumberhasexactly8positivedivisors,including35and77.Thisnumberis____

方法篇——KeywordsApositive36方法篇——Keywords

Whatisthesumofthemean,median,andmodeofthenumbers2,3,0,3,1,4,0,3?方法篇——KeywordsWhatisthe37方法篇——Keywords方法篇——Keywords38方法篇——Keywords

Whichofthefollowingfigureshasthegreatestnumberoflinesofsymmetry?(A)equilateraltriangle(B)non-squarerhombus(C)non-squarerectangle(D)isoscelestrapezoid(E)square方法篇——KeywordsWhichofth39

Thenumbers1,2,3……9areplacedinasquarearray.Thesumofthethreerows,thesumofthethreecolumns,andthesumofthetwodiagonalsareaddedtogethertoforma“grandsum”,S.Forexample,ifthenumbersareplacedasshown,thegrandsumis:S=rowsums+columnsums+diagonalsums=45+45+30=120.WhatisthemaximumpossiblevalueofthegrandsumS?方法篇——Keywords123456789Thenumbers1,2,3……9ar40方法篇Breakdown：化長為短，逐個(gè)擊破Keywords：尋找關(guān)鍵詞Son/Mother：圖文結(jié)合Miss/Pick：丟掉無用信息，留住有用信息方法篇Breakdown：化長為短，逐個(gè)擊破41

Whatistheareaoftheshadedpinwheelshowninthegrid?”(A)4(B)6(C)8(D)10(E)12方法篇——Son/MotherWhatistheareaofthesh42方法篇——Son/Mother

ThetwocirclespictureshavethesamecenterC.ChordADistangenttotheinnercircleatB,ACis10,andchordADhaslength16.Whatistheareabetweenthetwocircles?

(A)36π(B)49π(C)64π(D)81π(E)100π方法篇——Son/MotherThetwoc43方法篇——Son/MotherGiventheareasofthreesquaresinthefigure,theareaoftheinteriortriangleis________.

方法篇——Son/MotherGiventhe44方法篇——Son/MotherSemicirclesPOQandROSpassthroughthecenterofcircleO.WhatistheratioofthecombinedareasofthetwosemicirclestotheareaofthecircleO?

(A)(B)(C)(D)(E)方法篇——Son/MotherSemicircl45方法篇——Son/MotherAsinthefigure,theareaofsquareABCDis169,andtheareaofrhombusBCPQis156.Thentheareaoftheshadowpartis().(A)23(B)33(C)43(D)53方法篇——Son/MotherAsinthe46方法篇——Son/MotherAsshowninthefigure,pointCisonthesegmentBGandquadrilateralABCDisasquare.AGintersectsBDandCDatpointEandF.IfAE=5andEF=3,thenFG=________(A)16/3(B)8/3(C)4(D)5方法篇——Son/MotherAsshown47方法篇Breakdown：化長為短，逐個(gè)擊破Keywords：尋找關(guān)鍵詞Son/Mother：圖文結(jié)合Miss/Pick：丟掉無用信息，留住有用信息方法篇Breakdown：化長為短，逐個(gè)擊破48Ahauntedhousehassixwindows.InhowmanywayscanGeorgietheGhostenterthehousebyonewindowandleavebyadifferentwindow?方法篇——Miss/PickAhauntedhousehassixwi49方法篇——Miss/PickSixpepperonicircleswillexactlyfitacrossthediameterofa12-inchpizzawhenplacedasshown.Ifatotalof24circlesofpepperoniareplacedonthispizzawithoutoverlap,whatfractionofthepizzaiscoveredbypepperoni?(A)1/2(B)2/3(C)3/4(D)5/6(E)7/8方法篇——Miss/PickSixpeppe50方法篇——Miss/PickHuiisanavidreader.Sheboughtacopyofthebest-sellerMathisBeautiful.Onthefirstday,Huiread1/5ofthepagesplus12more,andontheseconddaysheread1/4oftheremainingpages,plus15pages.Onthethirdday,sheread1/3oftheremainingpages,plus18pages.Shethenrealizedthattherewereonly62pageslefttoread,whichshereadthenextday.Howmanypagesareinthisbook?(A)120(B)180(C)240(D)300(E)360方法篇——Miss/PickHuiisa51方法篇——Miss/PickAliceneedstoreplacealightbulblocated10centimetersbelowtheceilinginherkitchen.Theceilingis2.4metersabovethefloor.Aliceis1.5meterstallandcanreach46centimetersabovethetopofherhead.Standingonastool,shecanjustreachthelightbulb.Whatistheheightofthestool,incentimeters?(A)32(B)34(C)36(D)38(E)40方法篇——Miss/PickAlicenee52AMC8

專題講座AMC8專題講座53①①測(cè)試中心：TianjinTestCenter（Grade8）②姓名：LASTNAME為姓，F(xiàn)IRSTNAME為名姓名為4個(gè)字的同學(xué)，兩邊各寫兩個(gè)方框中一律左對(duì)齊，并在下方相應(yīng)位置填涂③性別：Female女Male男④不填涂⑤年級(jí)：按照實(shí)際情況填涂⑥年齡：按照實(shí)際情況填涂⑦考生簽字：中文姓名⑧不填涂⑨答題區(qū)域：每道題只有一個(gè)答案是正確的，將自己所選擇的答案的序號(hào)涂黑一律使用2B鉛筆任何填涂的位置必須完全覆蓋整個(gè)圓圈②③④⑤⑥⑦⑧⑨①①測(cè)試中心：②③④⑤⑥⑦⑧⑨54詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位55數(shù)number數(shù)字digit

個(gè)位unit

個(gè)位數(shù)字unitsdigit

十位數(shù)字tensdigit

百位數(shù)字hundredsdigit

千位數(shù)字thousandsdigit

三位數(shù)three-digitnumber詞匯篇——

數(shù)與數(shù)位1數(shù)number詞匯篇——數(shù)與數(shù)56實(shí)數(shù)realnumber

有理數(shù)rationalnumber

整數(shù)integer/wholenumber

正整數(shù)positiveinteger負(fù)整數(shù)negativeinteger自然數(shù)naturalnumber

奇數(shù)oddnumber/integer偶數(shù)evennumber/integer

因數(shù)factor/divisor公因數(shù)commonfactor/divisor質(zhì)因數(shù)primefactor/divisor

倍數(shù)multiple（最?。┕稊?shù)(least)commonmultiple

質(zhì)數(shù)primenumber合數(shù)compositenumber

分?jǐn)?shù)fraction

分子numerator分母denominator最簡分?jǐn)?shù)simplefraction

真分?jǐn)?shù)properfraction假分?jǐn)?shù)improperfraction帶分?jǐn)?shù)mixedfraction

繁分?jǐn)?shù)complexfraction

小數(shù)decimal

純小數(shù)decimalfraction無限小數(shù)infinitedecimal循環(huán)小數(shù)recurringdecimal

無理數(shù)irrationalnumber正數(shù)positivenumber負(fù)數(shù)negativenumber詞匯篇——

數(shù)與數(shù)位2實(shí)數(shù)realnumber詞匯篇——數(shù)與數(shù)位257值value絕對(duì)值absolutevalue倒數(shù)reciprocal/inverse平均值mean/average

加權(quán)平均數(shù)weightedaverage幾何平均數(shù)geometricaverage中位數(shù)median眾數(shù)mode平方數(shù)squarenumber

底數(shù)base冪exponent數(shù)列sequence

序數(shù)ordinal最大數(shù)maximum最小數(shù)minimum

等差（等比）數(shù)列arithmetic(geometric)sequence

連續(xù)的consecutive連續(xù)整數(shù)consecutiveinteger循環(huán)cycle詞匯篇——

數(shù)與數(shù)位3值value絕對(duì)值absolute58詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位59加add/plus和sum/total減subtract差difference乘multiply/times積product

乘方power階乘factorial除divide商quotientdividend÷divisor=quotient

divisible平方square平方根squareroot······remainder立方cube立方根cuberoot比例proportion比ratio公比commonratio詞匯篇——

運(yùn)算1加add/plus60增加increase

增加了increaseby增加到increaseto減少decrease/reduce

減少了decreaseby減少到decreaseto比較關(guān)系等于equal

不同distinct

估計(jì)estimation

近似approximate

大于morethan不大于nomorethan小于lessthan

四舍五入roundto詞匯篇——

運(yùn)算2增加increase詞匯篇——運(yùn)算261詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位62直線line/straightline端點(diǎn)endpoint線段segment中點(diǎn)midpoint平分bisect對(duì)稱symmetry相交intersect平行parallel平行線parallellines詞匯篇——

幾何圖形1直線line/straightline63平面plane陰影部分shadedregion詞匯篇——

幾何圖形2平面plane詞匯篇——幾何圖形264對(duì)角線diagonal周長perimeter/circumference面積area詞匯篇——

幾何圖形3詞匯篇——幾何圖形365正方形square

邊長side長方形（矩形）rectangle菱形rhombus梯形trapezoid等邊形equilateral多邊形polygon

正多邊形regularpolygon詞匯篇——

幾何圖形4詞匯篇——幾何圖形466角angle

銳角acuteangle直角rightangle鈍角obtuseangle平角straightangle周角roundangle詞匯篇——

幾何圖形5詞匯篇——幾何圖形567角angle

夾角includedangle角平分線anglebisector度degree分minute秒second詞匯篇——

幾何圖形6詞匯篇——幾何圖形668三角形triangle

頂點(diǎn)vertex（復(fù)數(shù)vertices）對(duì)邊oppositeside底邊base高h(yuǎn)eight/altitude內(nèi)角interiorangle外角exteriorangle中位線medianofatriangle詞匯篇——

幾何圖形7詞匯篇——幾何圖形769三角形triangle

等邊三角形equilateraltriangle

正三角形regulartriangle等腰三角形isoscelestriangle不等邊三角形scalenetriangle詞匯篇——

幾何圖形8詞匯篇——幾何圖形870三角形triangle

直角三角形righttriangle斜三角形obliquetriangle銳角三角形acuteangledtriangle鈍角三角形obtuseangledtriangle

詞匯篇——

幾何圖形9詞匯篇——幾何圖形971直角三角形

垂直perpendicular直角邊leg斜邊hypotenuse勾股定理Pythagoreanproposition詞匯篇——

幾何圖形10詞匯篇——幾何圖形1072圓circle/round

圓心centerofacircle直徑diameter半徑radius切線tangent詞匯篇——

幾何圖形11詞匯篇——幾何圖形1173

半圓semicircle扇形sector圓心角centralangle詞匯篇——

幾何圖形12詞匯篇——幾何74立體solid

表面積surfacearea體積volume

橫截面crosssection深度depth正多面體regularsolid/polyhedron長方體rectangularsolid圓柱體cylinder/circularcylinder圓錐cone球體sphere

詞匯篇——

幾何圖形13立體solid詞匯篇——幾何圖形1375詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位76

米meter千米kilometer

分米decimeter厘米centimeter

毫米millimeter微米micron

碼yard英尺foot英寸inch

克gram千克kilogram

加侖gallon夸脫quart品脫pint詞匯篇——

單位名稱米meter77詞匯篇數(shù)與數(shù)位運(yùn)算幾何圖形單位名稱商業(yè)詞匯詞匯篇數(shù)與數(shù)位78美元dollar美分cent1美分硬幣penny5美分硬幣nickel10美分硬幣dime25美分硬幣quarter價(jià)格price

成本價(jià)costprice

標(biāo)價(jià)listprice零售價(jià)retailprice

利潤profit利息interest詞匯篇——

商業(yè)詞匯美元dollar79方法篇Breakdown：化長為短，逐個(gè)擊破Keywords：尋找關(guān)鍵詞Son/Mother：圖文結(jié)合Miss/Pick：丟掉無用信息，留住有用信息方法篇Breakdown：化長為短，逐個(gè)擊破80Ms.Osborneaskseachstudentinherclasstodrawarectanglewithintegersidelengthsandaperimeterof50units.Allofherstudentscalculatetheareaoftherectangletheydraw.Whatisthedifferencebetweenthelargestandsmallestpossibleareasoftherectangles?(A)76(B)120(C)128(D)132(E)136

方法篇——BreakdownMs.Osborneaskseachst81方法篇——BreakdownChandlerwantstobuya$500mountainbike.Forhisbirthday,hisgrandparentssendhim$50,hisauntsendshim$35andhiscousingiveshim$15.Heearns$16perweekforhispaperroute.Hewilluseallofhisbirthdaymoneyandallofthemoneyheearnsfromhispaperroute.Inhowmanyweekswillhebeabletobuythemountainbike?(A)24(B)25(C)26(D)27(E)28方法篇——BreakdownChandlerw82方法篇——Breakdown

Picktwoconsecutivepositiveintegerswhosesumislessthan100.Squarebothofthoseintegersandthenfindthedifferenceofthesquares.Whichofthefollowingcouldbethedifference?(A)2(B)64(C)79(D)96(E)131方法篇——BreakdownPicktwoc83方法篇——BreakdownEverydayatschool,Joclimbsaflightof6stairs.Jocantakestairs1,2,or3atatime.Forexample,Jocouldclimb3,then1,then2stairs.InhowmanywayscanJoclimbthestairs?(A)13(B)18(C)20(D)22(E)24方法篇——BreakdownEveryday84方法篇Breakdown：化長為短，逐個(gè)擊破Keywords：尋找關(guān)鍵詞Son/Mother：圖文結(jié)合Miss/Pick：丟掉無用信息，留住有用信息方法篇Breakdown：化長為短，逐個(gè)擊破85方法篇——KeywordsThesmallestpossibleaverageoffourdistinctpositiveevenintegersis______.方法篇——KeywordsThesmalles86Mindymadethreepurchasesfor$1.98,$5.04and$9.89.Whatwashertotal,tothenearestdollar?(A)$10(B)$15(C)$16(D)$17(E)$18

方法篇——KeywordsMindymadethreepurchas87方法篇——Keywords

Apositivewholenumberhasexactly8positivedivisors,including35and77.Thisnumberis____

方法篇——KeywordsApositive88方法篇——Keywords

Whatisthesumofthemean,median,andmodeofthenumbers2,3,0,3,1,4,0,3?方法篇——KeywordsWhatisthe89方法篇——Keywords方法篇——Keywords90方法篇——Keywords

Whichofthefollowingfigureshasthegreatestnumberoflinesofsymmetry?(A)equilateraltriangle(B)non-squarerhombus(C)non-squarerectangle(D)isoscelestrapezoid(E)square方法篇——KeywordsWhichofth91

Thenumbers1,2,3……9areplacedinasquarearray.Thesumofthethreerows,thesumofthethreecolumns,andthesumofthetwodiagonalsareaddedtogethertoforma“grandsum”,S.Forexample,ifthenumbersareplacedasshown,thegrandsumis:S=rowsums+columnsums+diagonalsums=45+45+30=120.WhatisthemaximumpossiblevalueofthegrandsumS?方法篇——Keywords123456789Thenumbers1,2,3……9ar92方法篇Breakdown：化長為短，逐個(gè)擊破Keywords：尋找關(guān)鍵詞Son/Mother：圖文結(jié)合Miss/Pick：丟掉無用信息，留住有用信息方法篇Breakdown：化長為短，逐個(gè)擊破93

Whatistheareaoftheshadedpinwheelshowninthegrid?”(A)4(B)6(C)8(D)10(E)12方法篇——Son/MotherWhatistheareaofthesh94方法篇——Son/Mother

ThetwocirclespictureshavethesamecenterC.ChordADistangenttotheinnercircleatB,ACis10,andchordADhaslength16.Whatistheareabetweenthetwocircles?

(A)36π(B)49π(C)64π(D)81π(E)100π方法篇——Son/MotherThetwoc95