[PDF] Cambridge Secondary Checkpoint - Math (1112) October 2015 Paper 1 MS.pdf | Plain Text

This document consists of 11 printed pages and 1 blank page. IB15 10_1112_01/4RP © UCLES 2015 [Turn over Cambridge International Examinations Cambridge Secondary 1 Checkpoint MATHEMATICS 1112/01 Paper 1 October 2015 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.

2 © UCLES 2015 1112/01/O/N/15 Question number 1 Part Mark Answer Further Information (a) 1 16 41 or 4.41 pm (b) 1 19 min(utes) Total 2 Question number 2 Part Mark Answer Further Information (a) 1 53 and 59 in either order (b) 1 A correct reason e.g.  3 goes into 51  17 is a factor of 51  3 ×17  51 can be divided by 3 Total 2 Question number 3 Part Mark Answer Further Information (a) 1 All points plotted correctly (b) 1 (– 4,–2) or (– 4,6) Allow follow through from part (a) provided this results in a parallelogram. Total 2

3 © UCLES 2015 1112/01/O/N/15 [Turn over Question number 4 Part Mark Answer Further Information 2 3 5 7 20 1 3 35 100 35 10 1 35 Award 1 mark for ● 1 correct answer with none incorrect ● 2 correct answers with at most one incorrect Total 2 Question number 5 Part Mark Answer Further Information 2 Draws a correct triangle within the constraints of the overlay. Award 1 mark for angle between 32-36° or Award 1 mark for line between 7.0 and 7.4 cm Total 2 Question number 6 Part Mark Answer Further Information (a) 1 130.2 (b) 1 20 17 8 or 40 34 8 or 10085 8 Total 2

4 © UCLES 2015 1112/01/O/N/15 Question number 7 Part Mark Answer Further Information 1 Completes the table correctly. sleep school travel eat play 12 5 1 2 4 180° 75° 15° 30° 60° Total 1 Question number 8 Part Mark Answer Further Information 2 0.7 × 10 70 × 0.01 7 ÷ 0.01 7 ÷ 0.10.07 0.7 7 70 700 Award 1 mark for at least two correct. Total 2 Question number 9 Part Mark Answer Further Information (a) 1 19 (b) 1 28 Total 2

5 © UCLES 2015 1112/01/O/N/15 [Turn over Question number 10 Part Mark Answer Further Information 1 125 or equivalent fraction Total 1 Question number 11 Part Mark Answer Further Information 2 m m 3 m 2 mm Award 1 mark for any 2 correct. Total 2 Question number 12 Part Mark Answer Further Information (a) 1 x  7x (or equivalent) and x  2x + 1 (or equivalent) (b) 1 Add 3 and then multiply by 4 An equivalent answer is Multiply by 4 and then add 12 Total 2

6 © UCLES 2015 1112/01/O/N/15 Question number 13 Part Mark Answer Further Information 2 48 (minutes) Award 1 mark for 1 km in 6 minutes, or 3 km in 18 minutes. or 5 30 × 8 seen (or equivalent) or 0.8 seen Total 2 Question number 14 Part Mark Answer Further Information (a) 1 4n (b) 2 3 n + 4 or equivalent Award 1 mark for 3 n + c or Award 1 mark for k n + 4 where k  0 Total 3

7 © UCLES 2015 1112/01/O/N/15 [Turn over Question number 15 Part Mark Answer Further Information 1 There are (three) pairs that each add up to 10 Do not accept 30 as an answer without any explanation. Total 1 Question number 16 Part Mark Answer Further Information 2 6 5 Award 1 mark: for a correct unsimplified answer e.g. 12 10 or for a correct method e.g. 4 3 × 9 10 Total 2

8 © UCLES 2015 1112/01/O/N/15 Question number 17 Part Mark Answer Further Information 3 ( x = ) 2.5 or equivalent Award 2 marks for sight of 9 – 6 x and a simplified equation of the form  (-)8 x = c  ax = (-)20 where a and c are whole numbers. Award 1 mark for  sight of 9 – 6 x or  correct follow through from their expansion to reach an equation of the form ax = b . Total 3 Question number 18 Part Mark Answer Further Information (a) 1 11 (b) 1 5 Total 2 Question number 19 Part Mark Answer Further Information 1 −4 −3 −2 −1 0 1 2 3 4 −5 5 Total 1

9 © UCLES 2015 1112/01/O/N/15 [Turn over Question number 20 Part Mark Answer Further Information 1 3880 (Hong Kong dollars) Total 1 Question number 21 Part Mark Answer Further Information 3 ( a =) 64 (°) (b =) 32 (°) (c =) 84 (°) Award 2 marks in any of these cases:  two of a, b, c are correct  a = 64 and their a + b + c = 180  their b = 2a their and their a + b + c = 180 Award 1 mark in any of these cases:  one of a, b, c is correct  their b = 2a their  their a + b + c = 180 Total 3

10 © UCLES 2015 1112/01/O/N/15 Question number 22 Part Mark Answer Further Information 2 Enlargement and Scale factor 3 (or s.f. 3 or 3 times bigger) and (centre) (0, 1) Award 1 mark for stating 1 of these 3 parts of the description. Total 2 Question number 23 Part Mark Answer Further Information 1 48 Total 1 Question number 24 Part Mark Answer Further Information 2 Award 1 mark for a reason that relates to sample size, e.g.  10 is not enough people  She should ask more people and Award 1 mark for a reason that suggests that a wider range of people should be asked, e.g.  She should also ask people not waiting at the cinema  She should ask a wider range of people  She is only asking people who are visiting the cinema  She should collect data from more than one day Do not accept ‘Her results will be biased’ unless accompanied with further exemplification. Total 2

11 © UCLES 2015 1112/01/O/N/15 Question number 25 Part Mark Answer Further Information 2 12.5 km/h or 12500 m/h or 208.33.. m/min or 3.472.. m/s or equivalent using a different unit of speed or number as fraction Award 1 mark for a correct numerical value. or Award 1 mark for any unit of speed e.g. m/s, km/min seen. Total 2 Question number 26 Part Mark Answer Further Information 1 30090 (or equivalent) Do not accept ratios. Total 1 Question number 27 Part Mark Answer Further Information 2 (A) B CD Award 1 mark if two of B, C and D are correctly placed. Total 2

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