Secondary Express Math Mindmaps

-dary 2ExpressNotes - TESTCOMMONFACTOR(HCF) definitionarefactorisation ①Lookfor commonfactors. ②Ta kethenumberwiththe ⑪. RA TIONALNumBERS * smallestpower mersthat canbe expressedas S LOWESTCommonMUL TIPLE(LCM) fractions - i. e. 2 = 2, 0. 5 = 5, 0. =I ①Lookforcommonfactors . &IRRATIONALNUMBERS & Ta kethe numberwiththe - best power . - numbersthatcannotbeexpressed ③Multiplythemtogetherwiththe as fractions al otheruncommonnumbers . i. e. 12, I , . . . . E. g. FindHCFandLCMof36and64· ③ NUMBERS 36= 22x32 - numbersthatcanbedividedonly byitselfand1 . b SIGNIFICANT 64 = 26 i. 2. 2, 3, 5, 7.... -- FIGURES Thus, HCF = 2 2 = 4 ④INTEGERS * zeroesin betweennon-zerodigitsare significant LCM = 20x 32 = 576 - i. e. 5. 003 = 4significantfigures - wholenumbers * zeroesin frontofdecimalsarenotsignificant i. e. .-1 , 0, 2, . . . . i. e. 0. 00305=3significantfigures * zeroesbehinddecimalpointis significant . i.e.. 4. 000 = 4significantfigures - * zeroesbehindin wholenumbersmayor maynotbe significant . i. e. 200 = 1/2/3significantfigures .

W mustbe inthesameunits · PAPROPORTION⊥ cannotbeinfractionnordecimals If yisdirectlyproportionaltos, then properties N SCALE * y = kx bothunitsare incm) map scales ↑ SE PROPORTION AREASCALE If yis in proportional toce, thee Fin -- L E. g. (a)Giventhat2cmrepresents5km, i. e. Giventhatyis directlyproportionaltoC findthescaleintheform1 : m. andy = 12when = 2, findanequation M: A connectingyandx . -- 2cm : 5 km Step1 : Formequation = > y = kx2 :. k= 3 1 cm : 250000cm 1cm : 2. 5km M Step2 : Findconstantvalue, k. = 12= k(24 Step3: substituteKintoequation. = y = 3x* #1 : 250000# (b)If theareaonthemapis 5cm, find theactualarea, in km2 · distance= speedx time AA · speed= distance - 1cm: 2. 5km (mapscale) time distance· time=-(1cm)2 : (2. 5km speed 1cm2 : 6. 25km2Careascale) · AVERAGESPEED 5cm2: 31. 25kmA =total distancetaken - totaltime taken.

E. g. GiventhatSGD$1=Us$1. 30, PROFIT - findhowmuchAaronwillget, · monigetes PROF omLosS - gainmoneyfromthedeal if hewantstoexchangeUS$100· sellingprice - costprice us $1. 30-> SGD$1 Loss US$10U-> SGD$(b) -losemoneyfromthedeal. Es Iatt price - sellingprice = $76. 92# S - DME TAX * FAXATION- C TERESTBSIN - Income - whereP= principalCamtof$$Iloan/invest)I ble=AnnualGross totriesi ⊥↑ RE PURCHASEStrate 100 - E . g . T= time(unitsmustbeinyears) Alanearns$36, 000 in a year . Hegetswiferelief E. G . -- of $1000, childreliefof$500eachandNSreliefof$200. Danboughta TVset on hirepurchase . TheTVcosts$3500 . Hepaida downpayment Hehasthreechildren. Calculatetheamountof taxhe RVICE of10%andpaidthe balanceover a period CHARGE of2yearsat a rateof 2%perannum. hasto pay , - Calculatehismonthlyinstalment . Income * GSTisalwayscalculated -SOLUTION afterservicecharge Balance = 90%of$3500= $3150 - ⊥Freeincome , pari is addedto the bill. - 100 First$20000 0 ⑧ - Interest = $2X2 = $126- ~M Totalhehasto pay = $3150+$126 LOOK09 350 = $3276 ⑧ = $33300 : monthlyinstalments=$t * ChargeableIncome = $36, 000 - ($1000 + $1500 + $200