BVSS 2024 Prelim EM Paper 1 (Marking Scheme)

Answer all the questions. 1. Evaluate 34.5 23.4 8.17 , leaving your answer correct to 4 significant figures. Answer ……………….………….. [1] ---------------------------------------------------------------------------------------------------------------- 2. Express the ratio 21 3 kg : 450 g : 300 g in its simplest form. Answer ……… : ..……. : ……… [2] ---------------------------------------------------------------------------------------------------------------- 3. The Mathematics grades of students in Class A and Class B are summarised on accurate pie charts shown below. For each statement, state whether you agree or disagree and explain your reason. Statement Agree / Disagree Reason (a) More students in Class A failed Mathematics compared to Class B. Disagree We do not know the total number of students in each class. ----- B1 (b) The percentage of students who achieved A1-A2 are the same for both classes. Agree The proportion/percentage is 90 1 360 4= for A1-A2 for both classes. ----- B1 [2] A1-A2 B3-C6 D7-F9 Class B 2.306 ----- B1 5000 3 g : 450 g : 300 g ----- M1 (convert first number to g) 5000 : 1350 : 900 100 : 27 : 18 -------- A1 ( S4E/5N EM Prelim 2024 Paper 1 Marking Scheme A1-A2 B3-C6 D7-F9 Class A

2 4. A regular polygon has n sides. The size of each interior angle is 5 times the size of each exterior angle. (a) Calculate the value of each exterior angle. Answer ………….………….. [1] (b) State the value of n. Answer n = ……….…………. [1] ---------------------------------------------------------------------------------------------------------------- 5. The radius, r, of an object is directly proportional to the square root of its surface area, A. (i) Sketch the relationship between r and A on the space below. r ------ B1 A [1] (ii) The surface area of the object is 1.21 cm2 when the radius is 0.44 cm. Find the surface area of the object when the radius is 1.2 cm. Answer ………….………….. cm2 [2] ---------------------------------------------------------------------------------------------------------------- 5x + x = 180 x = 30 ------- B1 360 30n== 12 ------- B1 r k A= 0.44 1.21k= ------- M1 0.4k = 0.4rA= 1.2 0.4 A= 3 A= 9A= cm2 ------- A1

3 6. (a) Expand and simplify 2(4 1) 2x−+ . Answer ………….………….. [1] (b) Hence, or otherwise, explain if 2(4 1) 2x−+ is always odd, given that x is an integer. Answer : ……………………………………………………………………………… ………………………………………………………………………………………... ……………………………………………………………………………….…… [2] ---------------------------------------------------------------------------------------------------------------- 7. (a) Write down the set represented by the shaded region. Answer ……………………..…………. [1] (b) It is given that 𝜉 = { x : x is an integer}, A = {x : 9x } and B {2, 4, 6, 8}. State and explain whet