Mark Scheme (Results) Summer Pearson Edexcel International GCSE Mathematics A (4MA0/4HR) Paper 4HR

Transcription

1 Mark Scheme (Results) Summer 014 Pearson Edexcel International GCSE Mathematics A (4MA0/4HR) Paper 4HR

2 Edexcel and BTEC Qualifications Edexcel and BTEC qualifications come from Pearson, the world s leading learning company. We provide a wide range of qualifications including academic, vocational, occupational and specific programmes for employers. For further information, please visit our website at Our website subject pages hold useful resources, support material and live feeds from our subject advisors giving you access to a portal of information. If you have any subject specific questions about this specification that require the help of a subject specialist, you may find our Ask The Expert service helpful. Pearson: helping people progress, everywhere Our aim is to help everyone progress in their lives through education. We believe in every kind of learning, for all kinds of people, wherever they are in the world. We ve been involved in education for over 150 years, and by working across 70 countries, in 0 languages, we have built an international reputation for our commitment to high standards and raising achievement through innovation in education. Find out more about how we can help you and your students at: Summer 014 Publications Code UG03944 All the material in this publication is copyright Pearson Education Ltd 014

3 General Marking Guidance All candidates must receive the same treatment. Examiners must mark the first candidate in exactly the same way as they mark the last. Mark schemes should be applied positively. Candidates must be rewarded for what they have shown they can do rather than penalised for omissions. Examiners should mark according to the mark scheme not according to their perception of where the grade boundaries may lie. There is no ceiling on achievement. All marks on the mark scheme should be used appropriately. All the marks on the mark scheme are designed to be awarded. Examiners should always award full marks if deserved, i.e. if the answer matches the mark scheme. Examiners should also be prepared to award zero marks if the candidate s response is not worthy of credit according to the mark scheme. Where some judgement is required, mark schemes will provide the principles by which marks will be awarded and exemplification may be limited. When examiners are in doubt regarding the application of the mark scheme to a candidate s response, the team leader must be consulted. Crossed out work should be marked UNLESS the candidate has replaced it with an alternative response. Types of mark o M marks: method marks o A marks: accuracy marks o B marks: unconditional accuracy marks (independent of M marks) Abbreviations o awrt answers which round to o cao correct answer only o ft follow through o isw ignore subsequent working o SC - special case o oe or equivalent (and appropriate) o dep dependent o indep independent o eeoo each error or omission

4 No working If no working is shown then correct answers normally score full marks If no working is shown then incorrect (even though nearly correct) answers score no marks. With working If there is a wrong answer indicated on the answer line always check the working in the body of the script (and on any diagrams), and award any marks appropriate from the mark scheme. If it is clear from the working that the correct answer has been obtained from incorrect working, award 0 marks. Any case of suspected misread loses A (and B) marks on that part, but can gain the M marks. If working is crossed out and still legible, then it should be given any appropriate marks, as long as it has not been replaced by alternative work. If there is a choice of methods shown, then no marks should be awarded, unless the answer on the answer line makes clear the method that has been used. If there is no answer on the answer line then check the working for an obvious answer. Ignoring subsequent work It is appropriate to ignore subsequent work when the additional work does not change the answer in a way that is inappropriate for the question: eg. Incorrect cancelling of a fraction that would otherwise be correct. It is not appropriate to ignore subsequent work when the additional work essentially makes the answer incorrect eg algebra. Transcription errors occur when candidates present a correct answer in working, and write it incorrectly on the answer line; mark the correct answer. Parts of questions Unless specifically allowed by the mark scheme, the marks allocated to one part of the question CANNOT be awarded in another.

5 Apart from Questions 14 and 16 (where the mark scheme states otherwise), the correct answer, unless clearly obtained by an incorrect method, should be taken to imply a correct method. NB: All ranges for correct answers on the mark scheme are inclusive. 1 eg. = 5 p 4 5 or 5p = M1 for correct substitution (must be into a correct equation) eg. = 5p + 0 or M1 for correct simplification 0 (minimum of 4 5 = +0) 5p = 0 or p = oe 4 A1 (accept or 8 oe) 5 5 Total 3 marks

6 7 M1 for correctly converting 3h 7m into a 3.45 or 3 60 decimal (eg. 3.45) For '3h 7m' there must be some indication that this is the elapsed time from 0:07 to 3:34 7 "3 " 4 60 or M1 (independent) allow '3h 7m' 4 or For '3h 7m' there must be some indication that this is the elapsed time from 0:07 to 3:34 NB gets M A1 accept 773 Total 3 marks 3 (a) M1 for 3n + k (k may be zero) oe 3n + 1 oe A1 need not be simplified eg (n 1) NB: n = 3n + 1 gains M1 A0 (b) 3n + 1 =88 or (88 1) 3 M1 ft "3n + 1" =88 NB. Only ft if their expression is of the form an + b where a > 1 and b 0 9 A1 ft NB. unrounded answer must be an integer Total 4 marks

7 4 (a) Rotation, 90 o, anticlockwise, centre O 3 B1 Rotate or rotated B1 90 o (anticlockwise) or 70 o or 70 o clockwise B1 (centre) O or (0,0) or origin 0 (do not accept but do not count as an additional transformation) 0 (b) triangle at (6,1) (7,1) (7,3) NB if more than one transformation then 0 marks 1 B1 cao Total 4 marks 5 π 3 (= 9π) (= ) M1 rounded or truncated to 3 or more sig figs 0 1 (= 40) M M1 dep on M A1 for answer in range Total 4 marks

8 6 Working with all 1 boxes 1 15 (=180) or 1 1 (=144) M1 for correct total cost or correct total number of drinks (either may appear as part of another calculation) 3 M1 for revenue from all full price drinks sold oe ( = 16) oe (=07) or M1 for total revenue or total profit oe (=7) "07" "16" or 45 "7" + ("180" "16") M1 dep on M3 or A1 cao Total 5 marks Alternative working with one box (=1.5) or 1 ( = 9) 4 M1 for price of 1 drink or number of full price drinks 3 M1 for revenue from all full price drinks sold oe ( = 13.5) (=17.5) M1 for total revenue from one box "17.5" "13.5" 3 or A1 cao M1 dep on M3 Total 5 marks

9 7 (a) 0.9 oe 1 B1 accept 90% or 9 oe (b) oe M A1 cao Total 3 marks 8 (a) 5 = 16 = 63 = 3 1 M1 for a process that isolates at least correct prime factors e.g. 5 = 16, 16 = 3 4 or a factor tree with primes from, 3 or 7 identified or repeated division A1 for oe with correct prime factors (b) M1 " 3 7" 3 5 or a fully correct factor tree or fully correct repeated division A1 cao accept in any order Total 4 marks

10 9 x + 4 = 4x 30 M1 for forming a correct equation in x x = 18 A1 cao x + y + x + 4 = 180 or x + y + 4x 30 = 180 or x + y + 4x 30 + x x + y =360 M1 for forming a correct equation in x and y or a correct equation in y (NB. Their found value of x (which may not be correct) may be substituted) y = 60 4 A1 cao Total 4 marks (a).1 ( ) (= 0.35) or ( ) or.1 6 oe M1 allow.1 ( ) 3 (=1.05) for the method mark 0.7 A1 (accept 0.70) (b) eg. 6 3 = and 0.75 or oe M1 for a complete method 1.5 A1 cao Total 4 marks

11 11(a) d = 4 8 or 7, 7, 8, (x) or 4 8 (=3) M1 A1 (accept 7, 7, 8, on answer line) (b) ( "7" 3) + ( "7" 3) + ( "8" 3) + ( "" 3) 4 or or M1 ft for a complete method using candidate s 4 numbers from (a) or a 3+ b 3+ c 3+ d 3 oe A1 cao Total 4 marks

12 1 (a) M1 (t ± 1)(t ± 3) or (t ± 3)(t ± 1) NB. Accept 1t in place of t (b) bx = a y or (t 1)(t 3) A1 cao bx = y a M1 for isolating bx (or bx ) x = a y b or x = y a b or y a x = b x = ± a y b 3 M1 for isolating x y a y a A1 or x = ± or x =± b b (condone omission of ±) Total 5 marks 13 (a) M1 arrange in order or One of 1(median), 17(LQ), 3(UQ) identified (b) ( ) ( ) and ( ) 3-17 Carmelo and reason using IQR 6 3 A1 cao M1 Identify any two of 1, 17 and 3 B1 ft from (a) Carmelo - he has a lower IQR oe (IQR must be part of the statement) Total 5 marks

13 14 (a) or oe or 8 00 or M1 for correct conversion from m to km or from km to m or M1 (indep) award for digits 975 (eg. an answer of gets M0 M1 A0) A1 cao (b) 1.95 km B1 cao M1 ft from (a) also award for (=0.(km)) or 13 "9.75 " "9.75 " or 1.95 "9.75 " "9.75 " (=00(m))or 8 (=00(m)) or or 8 or (=00(m)) NB: 1.95 may be the candidate s upper bound 00 3 A1 cao must be from correct figures used in a correct calculation Total 6 marks

14 15 (a) 3 then two pairs of branches with, on the W and R branches respectively M1 on lower LH branch OR 7 two additional pairs branches labelled with white and red fully correct tree diagram A1 for fully correct tree diagram with all probabilities and labels NB: Accept rounded or truncated to 3 or more sig figs for 7 (b) (c) 5 3 " " M1 ft from their tree diagram A1 oe eg. 3 or rounded or 35 7 truncated to 3 or more sig figs Accept 0.43 if working shown M1 for a correct M for " "or " " product only ft 15 probabilities < 1 1 " " " " " " M1 for full method " " + " " A1 oe accept decimal answer rounded or truncated to 3 or more sig figs Accept 0.46 if working shown Total 7 marks

15 16 (a) Eg. Area = (4x 3)( x+ 1) + [ 3 x ( x+ 1) ] 4 OR M1 for a complete correct expression for area of hexagon Area = 4 3x + ( x + 1)(4x 3 4) OR Area = (4x 3) 3x (4x 3 4)(3 x ( x+ 1)) (b) 9 ± ( 47) 4 A1 for all brackets correctly expanded Answer given 3 A1 for convincing progression to given equation M1 for correct substitution; condone one sign error; brackets not necessary; condone + instead of ± in formula There may be partial evaluation if so, this must be correct 833 or or 7 17 or M1 (independent) for correct simplification of discriminant (if evaluated, at least 3sf rounded or truncated) (c) 3 ".48"... (=7.44 ) or 4 ".48" 3 (=6.93 ).48, A1 awrt.48 and 4.73 NB. If negative solution is discarded (or omitted at any stage) then full marks can still be obtained Award 3 marks if first M1 scored and answer correct M A1 for

16 16b Alternative 9 47 x + x = ( x + ) = ( x + ) =± 8 64 M1 9 for ( x + ) oe 8 M for ( x + ) =± oe , A1 awrt.48 and 4.73 NB. If negative solution is discarded (or omitted) then full marks can still be obtained Award 3 marks if first M1 scored and answer correct Total 8 marks

17 17 (a) 4x y B (b) (B1 for ax n y m with two of a = 4; n = ; m = 1) (x )(x + ) or (x 4)(x + ) or (x )(x + 4) M1 for numerator factorised 4x(x ) or x(x 4) M1 for denominator factorised Alternative to (b): x 8 x 4 ( x )( x+ ) = = 4x 8x x 4x xx ( ) x x + 3 x + x A1 accept x 3 In order to use this mark scheme, correct simplification of the original fraction must be seen M1 (x )(x + ) M1 x(x ) A1 accept x Total 5 marks

18 18 (a) AOC= B1 cao (b) Using angle CGF = angle FGE + angle CGE Angle between tangent and radius is 90 o B1 for Angle between tangent and radius is 90 o (accept right-angle or perpendicular) FGE = (=56) M1 may be on diagram CGE = "54" (=7) or 180 (180 "54") (=7) Alternative: Using angles in a cyclic quadrilateral = 180 o Angle CGF = 180 (angle CEO + angle FEG) Angle CEO = ( ) (=63) and angle FEG = 180 (180 70) 36) (=34) Angle CGF = 180 ( ) M1 may be on diagram 83 3 A1 cao M1 may be on diagram M1 dep on previous M A1 cao Total 5 marks

19 19 (BC = ) cos o ( = 79.7) M1 correct use of Cosine rule to find BC (BC = ) (=79.7) M1 correct order of operations A1 for BC = or sin C sin = or 6.4 "8.9.." 6.4 = cosc sin C = (= 0.6 ) or "8.9.." "8.9" 6.4 cos C = (=0.78 ) 3.8 "8.9" C = Alternative CD is the perpendicular from C to BA produced. CAD = 60 o or ACD = 30 o AD = 3.8 cos60 o or 3.8sin30 (= 1.9) or 5 oe M1 correct use of Sine rule or Cosine rule to find angle C M1 correct rearrangement Award M A1 for BC = or 79.7 or oe Award M for C = Award M for B = 1.5 and C = 180 B A1 (0)68 (0)68.4 M1 uses triangle CAD and CAD = 60 o or ACD = 30 o CD may not be drawn in but can be implied M1 for correct method to find horizontal length BD = (= 8.3) A1 for BD = 8.3 CD = 3.8sin60 or 3.8cos30 (=3.9) M1 8.3 M1 tan BCD = oe 3.8sin A1 (0)68 (0)68.4 Total 6 marks

20 0 (Slant Height =) ( 5a ) + (1a) (= 13a) M1 correct use of Pythagoras condone missing brackets (total surface area = ) π (5a) + π 5a 13a oe or π (5a) + π 5a ( 5a ) + (1a) (=90 πa ) eg. 90 πa = 360π oe or π (5a) + π 5a 13a = 360π oe 1 π (5 "") 1 "" V = (=0πa 3 ) or 3 V = 1 π 4 3 oe or 1 k = (5 "") 1 "" A1 cao M1 dep on first M1 must have either 5a or (5a) M1 dep on first M1 for equation formed (need not be simplified) must have either 5a or (5a) A1 a = M1 dep on first M1 NB. For the award of this mark, brackets must be present or the value for r evaluated correctly for the candidate s value of a Total 6 marks

21 1 (a) LHS a c + a + c + 1 M1 for correct expansion of LHS RHS Shown 3 A1 for convincing progression and conclusion Alternative (i): M1 for correct expansion of LHS LHS a c + a + c + 1 a c ac + 1+ a + ac + c M1 for introduction of +ac and ac Shown 3 A1 for convincing progression and conclusion Alternative (ii) M1 for correct expansion of RHS RHS a c ac + 1+ a + ac + c a c ac + 1+ a + ac + c = a c + a + c + 1 M1 for correct simplification and convincing =a (c + 1) + (c + 1) factorisation Shown 3 A1 for convincing progression and conclusion M1 for a c ac + 1+ a + ac + c M1 for correct expansion of RHS (b) a= 8, c = 0 ac - 1 = a + c = A1 a= 8, c = 0 or a = 0 and c = 8 or 8 and 799 8, A1 8, 799 or and Total 6 marks TOTAL FOR PAPER: 0 MARKS

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