Practice Papers Set 1 Teacher Booklet GCSE MATHEMATICS. New Specimen Papers published June 2015 Paper 2 Foundation - Mark Scheme 8300/2F. Version 1.

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1 Practice Papers Set 1 Teacher Booklet GCSE MATHEMATICS New Specimen Papers published June 2015 Paper 2 Foundation - Mark Scheme 8300/2F Version 1.0

2 Principal Examiners have prepared these mark schemes f specimen papers. These mark schemes have not, therefe, been through the nmal process of standardising that would take place f live papers. Further copies of this Mark Scheme are available from aqa.g.uk Glossary f Mark Schemes GCSE examinations are marked in such a way as to award positive achievement wherever possible. Thus, f GCSE Mathematics papers, marks are awarded under various categies. If a student uses a method which is not explicitly covered by the mark scheme the same principles of marking should be applied. Credit should be given to any valid methods. Examiners should seek advice from their seni examiner if in any doubt. M A B ft SC M dep B dep Method marks are awarded f a crect method which could lead to a crect answer. Accuracy marks are awarded when following on from a crect method. It is not necessary to always see the method. This can be implied. Marks awarded independent of method. Follow through marks. Marks awarded f crect wking following a mistake in an earlier step. Special case. Marks awarded within the scheme f a common misinterpretation which has some mathematical wth. A method mark dependent on a previous method mark being awarded. A mark that can only be awarded if a previous independent mark has been awarded. Or equivalent. Accept answers that are equivalent. 1 eg accept 0.5 as well as 2 [a, b] Accept values between a and b inclusive Accept answers which begin 3.14 eg 3.14, 3.142, Use of brackets It is not necessary to see the bracketed wk to award the marks. Page 2 Version 1.0

3 MARK SCHEME GCSE MATHEMATICS UPDATED SPECIMEN PAPERS PAPER 2 FOUNDATION Examiners should consistently apply the following principles Diagrams Diagrams that have wking on them should be treated like nmal responses. If a diagram has been written on but the crect response is within the answer space, the wk within the answer space should be marked. Wking on diagrams that contradicts wk within the answer space is not to be considered as choice but as wking, and is not, therefe, penalised. Responses which appear to come from increct methods Whenever there is doubt as to whether a student has used an increct method to obtain an answer, as a general principle, the benefit of doubt must be given to the student. In cases where there is no doubt that the answer has come from increct wking then the student should be penalised. Questions which ask students to show wking Instructions on marking will be given but usually marks are not awarded to students who show no wking. Questions which do not ask students to show wking As a general principle, a crect response is awarded full marks. Misread miscopy Students often copy values from a question increctly. If the examiner thinks that the student has made a genuine misread, then only the accuracy marks (A B marks), up to a maximum of 2 marks are penalised. The method marks can still be awarded. Further wk Once the crect answer has been seen, further wking may be igned unless it gs on to contradict the crect answer. Choice When a choice of answers and/ methods is given, mark each attempt. If both methods are valid then M marks can be awarded but any increct answer method would result in marks being lost. Wk not replaced Erased crossed out wk that is still legible should be marked. Wk replaced Erased crossed out wk that has been replaced is not awarded marks. Premature approximation Rounding off too early can lead to inaccuracy in the final answer. This should be penalised by 1 mark unless instructed otherwise. Version 1.0 Page 3

4 Q Answer Mark Comments D 5 [8.4, 8.8] ( 2.5) [21, 22] SC1 Any given length in cm crectly multiplied by 2.5 Alternative method their dep sces M Alternative method their 110 their 77 dep 88 7(a) Yes, gives crect answer as inverse operations and der ds not matter 7(b) No, ds not wk, inverse operations not in crect der Page 4 Version 1.0

5 MARK SCHEME GCSE MATHEMATICS UPDATED SPECIMEN PAPERS PAPER 2 FOUNDATION Q Answer Mark Comments 8(a) 5w = w = (b) 15x + 12y 12y + 15x 8(c) 2x + y 2 y 2 + 2x 9 No and shows an example of an even multiple of 3 + a multiple of 2 = an even number eg No and = 10 Alternative method (0) (0) and Yes Alternative method (8 ) (8 ) 8.7 and Yes Alternative method ( ) ( ) 46 and Yes Alternative method (...) (...) 23 and Yes Version 1.0 Page 5

6 Q Answer Mark Comments Box C their Box A 11 their (A =) 19, (B =) 15, (C =) 28 SC2 f their A + their B = 34 and their A their C = ±9 SC1 f their A + their B = 34 their A their C = ±9 Alternative method their dep (= 140) 360 Alternative method 2 12(a) (800 their 380) 420 dep (= 140) Alternative method their = 171 Page 6 Version 1.0

7 MARK SCHEME GCSE MATHEMATICS UPDATED SPECIMEN PAPERS PAPER 2 FOUNDATION Q Answer Mark Comments Bar heights 380, 280 and 140 B2 f one crect bar height 280 seen 380 seen 12(b) Three bars with equal widths, equal gaps and crectly labelled vertical axis and bars labelled Consistent scale, starting at zero with at least two numbers given Must be using a scale of at least 1 cm per 100 sales 13(a) (...) (b) 34 ft ft their answer to (a) Version 1.0 Page 7

8 Q Answer Mark Comments Alternative method ( ) x = their 34 dep 102 Alternative method 2 14 Ratio 30 : 20 seen implied dep 102 Alternative method 3 Chooses 10p and 20p coins in the ratio 3 : 1 and wks out their total value Builds up to and 6.80 dep 102 Page 8 Version 1.0

9 MARK SCHEME GCSE MATHEMATICS UPDATED SPECIMEN PAPERS PAPER 2 FOUNDATION Q Answer Mark Comments 15(a) 12 15(b) ( )52.5(0) 4 63 ( )52.5(0) and No a = 9 Substitutes a crect pair of values f n and C into C = their 9 + b(n 1) 15(c) method f gradient eg b = 8 Sketch of possible pentagon with exactly one line of symmetry, integer sides labelled, perimeter 15 cm ie regular pentagon with 5 3 cm labelled cm and 4 2 cm 1 7 cm and 2 3 cm and 2 1 cm 1 5 cm and 2 4 cm and 2 1 cm 1 5 cm and 2 3 cm and 2 2 cm 1 3 cm and 2 5 cm and 2 1 cm B2 (impossible) pentagon with sides labelled eg 1 11 cm and 4 1 cm pentagon with one line of symmetry and non-integer sides labelled, perimeter 15 Units not needed 1 3 cm and 2 4 cm and 2 2 cm 3 1 cm and 2 6 cm 1 1 cm and 2 5 cm and 2 2 cm 1 1 cm and 2 4 cm and 2 3 cm 5 3 cm (but sketch clearly only has 1 line of symmetry) Version 1.0 Page 9

10 Q Answer Mark Comments Alternative method (miles) their [3.74, 3.75] (gallons) their [3.74, 3.75] 4.5 [16.8, 16.9] (litres) their [16.8, 16.9] [21.33, 21.47] and bus Accept 21 and bus if wking shown Alternative method (miles) their [3.74, 3.75] (gallons) (5) 5.72 their [3.74, 3.75] their 5.71(5) [21.33, 21.47] and bus Accept 21 and bus if wking shown Alternative methods 3 and 4 on next page Page 10 Version 1.0

11 MARK SCHEME GCSE MATHEMATICS UPDATED SPECIMEN PAPERS PAPER 2 FOUNDATION Q Answer Mark Comments Alternative method (0) [0.74, 0.75] (gallons) their [0.74, 0.75] 4.5 [3.3, 3.4] (litres) their [3.3, 3.4] [4.19, 4.32] and 3.9(0) and bus Accept 4 and 3.9(0) and bus if wking shown Alternative method (0) [0.74, 0.75] (gallons) (5) 5.72 their [0.74, 0.75] their 5.71(5) [4.19, 4.32] and 3.9(0) and bus per gallon Accept 4 and 3.9(0) and bus if wking shown Version 1.0 Page 11

12 Q Answer Mark Comments 7x 4 3x + 2 7x 4 = 3(3x + 2) 7x 4 = 9x x 9x = x = = 9x 7x Collecting like terms 10 = 2x = = = 400 Ticks No, the time will be longer and gives crect explanation eg He won t be able to run 10 km at same speed / rate / pace as he runs 400 m their Page 12 Version 1.0

13 MARK SCHEME GCSE MATHEMATICS UPDATED SPECIMEN PAPERS PAPER 2 FOUNDATION Q Answer Mark Comments S E B2 Any 2 3 of the 4 sections crect Any 1 of the 4 sections crect 22(a) B3 22(b) 1 12 ft ft their Venn diagram 23(a) Two of B2 fraction, decimal, percentage One of with at most one increct answer 23(b) Chooses their probability from the larger number of trials and reason given that me trials are involved ft Must have two probabilities in (a) 4 80% seen used 5 May be implied 29.4(0) (0) 4 ( 5) 7.35 ( 5) 29.4(0) AAA Version 1.0 Page 13

14 Q Answer Mark Comments Alternative method 1 6 and 10 seen (their 6) 2 + (their 10) dep [11.66, 11.7] Alternative method their [23.32, ] dep [11.66, 11.7] y = 5x + 2 Alternative method 1 2 parts Alternative method 2 Writes at least 3 ratios numbers of boys and girls equivalent to 9 : 7 eg 18 : 14 and 180 : 140 and 360 : and (x 4)(x + 8) = 0 Page 14 Version 1.0

15 MARK SCHEME GCSE MATHEMATICS UPDATED SPECIMEN PAPERS PAPER 2 FOUNDATION Q Answer Mark Comments Alternative method ( ) their their their their dep 30 1 ( ) and dep 1 (their ) their Must see wking = 294 Do not award without wking seen Alternative method ( ) (Area scale fact =) (their 2.5) 2 (their 0.4) 2 their 350 (their 2.5) 2 their 350 (their 0.4) 2 56 dep dep Must see wking = 294 Do not award without wking seen Version 1.0 Page 15

16 Copyright 2015 AQA and its licenss. All rights reserved. AQA retains the copyright on all its publications. However, registered schools/colleges f AQA are permitted to copy material from this booklet f their own internal use, with the following imptant exception: AQA cannot give permission to schools/colleges to photocopy any material that is acknowledged to a third party even f internal use within the centre. SP/02/15