[PDF] April 2018 CAIE P1 Mark Schemes 1112 Mathematics Lower Secondary Checkpoint.pdf | Plain Text
This document consists of 13 printed pages and 1 blank pages. IB18 05_1112_01/3RP © UCLES 2018 [Turn over Cambridge International Examinations Cambridge Secondary 1 Checkpoint M ATHEM ATICS 1112/01 Paper 1 April 2018 MARK SCHEME Maximum Mark : 50 IMPORTANT NOTICE Mark Schemes have been issued on the basis of one copy per Assistant examiner and two copies per Team Leader.
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 2 of 12 Mark scheme annotations and abbreviations M1 method mark A1 accuracy mark B1 independent mark FT follow through after error dep dependent oe or equivalent cao correct answer only isw ignore subsequent working soi seen or implied
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 3 of 12 Question Answ er Marks Further Information 1(a) 5 1 Allow +5 1(b) 7 8 oe 1 2 Ticks Lily and shows correct values for comparison , e.g. 160 pages (Lily) 144 pages (Safia) 2 Do not accept Lily without an explanation. Correct method, e.g. 0.32 × 500 oe implied by 160 or 0.4 × 360 oe implied by 144 M1 3 6 2 0.25 or 1500 seen. B1 4 A correct explanation relating to order of operations e.g. • Division should be done first • adding comes after dividing • Mike has done the calculations in the wrong order • 12 ÷ 4 = 3, 3 + 8 = 11 • He hasn’t used BODMAS 1 Do not accept • he hasn’t calculated correctly • the correct answer is 11 (alone) But accept • Using BODMAS, the answer should be 11 • Accept other acronyms e.g. BIDMAS, PEMDAS
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 4 of 12 Question Answ er Marks Further Information 5 2 one or two correct triangle s ringed with no more than one incorrect triangle ringed. B1 6(a) 1.2 1 6(b) 250 1 7(a) Grade A, B or C Grade D, E or F Total Boys 76 64 140 Girls 79 61 140 Total 155 125 280 2 at least 4 correct entries. B1 7(b) 61 280 1 Question Answ er Marks Further Information
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 5 of 12 8 + 3 a 4 7 7b 1 Accept a ny unambiguous indication of the correct answer . 9 2 and 4 and 10 in correct order 2 2 correct answers . B1 10 (a) 2x(x – 3) 2 Ignore attempt s to “solve” or expand back out either of • x(2 x – 6) • 2(x2 – 3x) M1
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 6 of 12 Question Answ er Marks Further Information 10 (b) 4 2 ) ( + = h r or 2 8 ) ( + = h r 2 correct first step, e.g. • sight of 2 r – 8 • sight of – = h r4 2 • sight of 2r = h + 8 M1 11 8 1 12 1 Accept any unambiguous indication of the correct answer. 13 7 12 1 cao 14 x2 + 6 x – 16 2 at le ast 3 out of these 4 terms seen : x2, 8 x, –2x, –16 + 6x implies both 8x and –2x. B1
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 7 of 12 Question Answ er Marks Further Information 15(a) Age of student Gender of student Time spent doing sport each week Favourite sport 1 Accept any unambiguous indication of the correct answer. 15(b) A correct explanation, e.g. • She is not asking enough people. • She should not just ask her friends . • Her friends may all be girls. 1 Accept equivalents, e.g. • She will not have enough data . • Her friends will not be representative of everyone in the school. ‘ask more friends’ 0 marks 16(a) 15 1 Do not accept 15 2 16(b) 1 Accept any unambiguous indication of the correct answer. 17 3600 4.7 20 000 2 In correct order. 2 correct answers . B1 18 2 1 Question Answ er Marks Further Information
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 8 of 12 19 250 000 (cm 3) 1 20 (m =) 3 1 21 (a) 1 21(b) 1 Accept c orrect f ollow through from an incorrect answer to part ( a) 21(c) (1, 2) 1 Accept f ollow through from correct intersection of their two mirror lines. 22(a) Shape B: 0 and 1 Shape C: 0 and 2 Shape D: 1 and 1 2 All 6 values correct for 2 marks . B1 3 or more values correct. 22 (b) Diagram of a square (or any other more complex diagram that has the correct symmetry properties) . 1 Properties need not be shown.
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 9 of 12 Question Answ er Marks Further Information 23 (a) (x =) 3.2 ( y =) 3.6 Allow ± 0.2 2 either x = 3.2 or y = 3.6 (allow ± 0.2) for either answer correct or x = 2.4 and y = 5.2 (allow ± 0.2) for correct intersection of pair of lines. B1 23 (b ) 2 For 2 marks line must go from (0,6) to (3,0) within a tolerance of half a small square at least two correct points are plotted e.g. (0,6), (1,4), (2,2), (3,0) or if the line is not drawn with a ruler B1
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 10 of 12 Question Answ er Marks Further Information 24 840 3 a correct method to find the number of boys, e.g. × × 18 20 4 3 implied by 480 or the correct method for finding the total number of students , e.g. × × 18 20 7 3 implied by 840 M2 18 × 20 or 18 ÷ 0.05 or sight of 360 or 42 or 24 or × 18 7 3 or × 18 4 3 M1 If M2 not scored.
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 11 of 12 Question Answ er Marks Further Information 25 Any correct expression e.g. x2 + 2 x – 15 (cm 2) or ( x + 5)( x – 3) (cm 2) 2 Allow unsimplified expression for 2 marks . ISW attempts to solve. Identifying one side as x + 5 or one side as x – 3, on the diagram or as part of a product or 3 out of 4 terms correct from x 2 + 5 x – 3 x – 15 2 x implies both 5 x and –3 x B1
1112/01 Checkpoint Secondary 1 – Mark Scheme April 2018 POST-STANDARDISATION © UCLES 2018 Page 12 of 12 BLANK PAG E
