Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Specification B – Practice Paper C Mark Scheme GCSE GCSE Mathematics (Modular) Paper: 5MB2F_01 GCSE MATHEMATICS UNIT 2 PRACTICE PAPER C MARKSCHEME NOTES ON MARKING PRINCIPLES 1 Types of mark M marks: method marks A marks: accuracy marks B marks: unconditional accuracy marks (independent of M marks) 2 Abbreviations cao – correct answer only isw – ignore subsequent working oe – or equivalent (and appropriate) indep - independent ft – follow through SC: special case dep – dependent 3 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. 4 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 If working is crossed out and still legible, then it should be given any appropriate marks, as long as it has not been replaced by alternative work.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 it is clear from the working that the “correct” answer has been obtained from incorrect working, award 0 marks. Send the response to review, and discuss each of these situations with your Team Leader. If there is no answer on the answer line then check the working for an obvious answer. Any case of suspected misread loses A (and B) marks on that part, but can gain the M marks. Discuss each of these situations with your Team Leader. 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. Paper: 5MB2F_01 Session: Practice Paper C 2 GCSE MATHEMATICS UNIT 2 PRACTICE PAPER C MARKSCHEME 5 Follow through marks Follow through marks which involve a single stage calculation can be awarded without working since you can check the answer yourself, but if ambiguous do not award. Follow through marks which involve more than one stage of calculation can only be awarded on sight of the relevant working, even if it appears obvious that there is only one way you could get the answer given. 6 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: e.g. incorrect canceling 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 e.g. algebra. Transcription errors occur when candidates present a correct answer in working, and write it incorrectly on the answer line; mark the correct answer. 7 Probability Probability answers must be given a fractions, percentages or decimals. If a candidate gives a decimal equivalent to a probability, this should be written to at least 2 decimal places (unless tenths). Incorrect notation should lose the accuracy marks, but be awarded any implied method marks. If a probability answer is given on the answer line using both incorrect and correct notation, award the marks. If a probability fraction is given then cancelled incorrectly, ignore the incorrectly cancelled answer. 8 Linear equations Full marks can be gained if the solution alone is given on the answer line, or otherwise unambiguously indicated in working (without contradiction elsewhere). Where the correct solution only is shown substituted, but not identified as the solution, the accuracy mark is lost but any method marks can be awarded. 9 Parts of questions Unless allowed by the mark scheme, the marks allocated to one part of the question CANNOT be awarded in another. 10 Use of ranges for answers If an answer is within a range this is inclusive, unless otherwise stated. Paper: 5MB2F_01 Session: Practice Paper C 3 GCSE MATHEMATICS UNIT 2 PRACTICE PAPER C MARKSCHEME Question (a) 1 2 Working Answer Mark (6, 7) 1 B1 cao (b) (3, 6) 1 B1 cao (c)(i) Plotting point 1 B1 for plotting point correctly (c)(ii) Plotting point 1 B1 for plotting point correctly (a) 1466 1 B1 cao (b) 561 1 3.85 2 (a) 4s 1 B1 cao M1 for 7.35 – 3.50 A1 cao B1 oe (b) 4ab 1 B1 oe (a) Parallel lines marked 1 B1 cao (b) Right angle marked 1 B1 cao (c)(i) Acute 1 B1 ignore spelling (c)(ii) reflex 1 B1 ignore spelling (a) 23 1 B1 cao (b) 47 1 95 2 90p or £0.90 3 B1 cao M1 for squaring 4 or multiplying out bracket A1 cao M1 for attempt to divide 18 by 20 A1 for 90 or 0.9 C1 for writing sum of money correctly 7.35 – 3.50 3 4 5 (c) 6 7 Paper: 5MB2F_01 Session: Practice Paper C 5(3 + 16) £18 ÷ 20 1800 ÷ 20 = 90 2.50 10.00 3.00 5.00 24.00 £3 £2.50 £24 £42 4 Notes B1 B1 B1 B1 for £3 for £2.50 for £24 ft for £42 4 GCSE MATHEMATICS UNIT 2 PRACTICE PAPER C MARKSCHEME Question (a) 8 9 Working Answer 82 Mark 1 (b) 70 1 (c) explanation 1 (d) 102 – 4n 2 (a) 1 more square 1 (b) 1 more square 1 (c) Correct shape 1 (d) Correct shape 1 10 23 –14 + 3 12 2 11 (56 ÷ 8) × (30 ÷ 6) × (36 ÷ 12) Or (56 × 30 × 12) ÷ (8 × 6 × 12) 105 3 12 Angle ABE = 65º (opposite angles of a parallelogram are equal) Angle x = 180 – 65 = 125 (angles in a straight line add to 180º) 125 4 Paper: 5MB2F_01 Session: Practice Paper C Notes B1 cao B1 cao C1 for explanation e.g. 23 is odd and all the members of the sequence are even M1 for linear term in – 4n (e.g. 98 – 4n) A1 for 102 – 4n B1 for a correct square added B1 for a correct square added B1 for a correct shape that has 2 lines of symmetry e.g. rectangle B1 for a correct shape with rotational symmetry of order 2 but no lines of symmetry e.g. parallelogram M1 for 23 – 14 + 3 oe A1 for 12 M1 for attempt to find the number of boxes along one length of a carton or attempt to find the volume of a box or the carton M1 for attempt to multiply their 7, 5 and 3 or divide their volumes A1 for 105 cao M1 for Angle ABE = 65º C1 for opposite angles of a parallelogram are equal M1 for Angle x = 180 – 65 = 125 C1 for angles in a straight line add to 180º 5 GCSE MATHEMATICS UNIT 2 PRACTICE PAPER C MARKSCHEME Question Working Answer Mark 256 54 × 1024 12800 13824 × 200 50 6 50 10000 2500 300 4 800 200 24 M1 for complete method for multiplying 200, 50 and 6 by 4 and 50 condone one error in multiplication M1 (dep) for addition condone one addition error A1 cao for 13 824 10 000 + 2500 + 300 + 800 + 200 + 24 = 13 824 13 2 1 5 1 2 0 8 8 y= –1 , , 3, 14 (b) Paper: 5MB2F_01 Session: Practice Paper C 3 0 2 0 2 , 7, 9 13 824 3 M1 for complete method for multiplying 2, 5 and 6 by 5 and 4 condone one error in multiplication M1 (dep) for addition condone one addition error A1 cao for 13 824 6 5 2 3 (a) Notes M1 for complete method for multiplying 256 by 4 and 50 condone one error in multiplication M1 (dep) for addition condone one addition error A1 cao for 13 824 4 5 4 4 Table of values Straight line from (−2, −1) 2 2 B2 for 4 values of y correct (B1 for 2 or 3 values correct) B2 for a correct straight line from (−2, −1) to (3, 9) [B1 ft for at least 5 correctly plotted points OR a single line passing through (0, 3) OR for a single line of 6 GCSE MATHEMATICS UNIT 2 PRACTICE PAPER C MARKSCHEME to (3, 9) Question Working = Mark 1800 3 (a) x9 1 (b) 4 y 1 18 5 15 16 = Answer gradient 2) 2×⅜=¾ 14 ÷ ¾ = 18⅔ 17 Paper: 5MB2F_01 Session: Practice Paper C Notes M1 for correct attempt to write 2 numbers correct to 1 significant figure M1 for correct attempt to establish 360 ÷ 0.2 A1 cao B1 cao B1 cao M1 for attempt to double ⅜ A1 for ¾ M1 for attempt to find how many ¾ there are in 14 by dividing or by counting on A1 for 18⅔ or realizing that it will me more than 18 C1 for rounding to 18 rather than 19 or sufficient explanation from their attempt at division 7