4NA KSS Practice WA1 2025 (QS)

4N WA1 (2022-2024) Revision Mathematical Formulae Compound Interest Total amount = Mensuration Curved surface area of a cone = rl Surface area of a sphere = 4r2 Volume of a cone = Volume of a sphere = Area of triangle ABC = Arc length = r , where  is in radians Sector area = , where  is in radians Trigonometry Statistics Mean = Standard deviation = n rP      + 1001 hr 2 3 1 3 3 4 r Cabsin2 1 2 2 1 r C c B b A a sinsinsin == Abccba cos2222 −+=   f fx 22       −     f fx f fx

2 Extracted from 4NA WA1 2024 1 X, Y and Z are three points lying in a horizontal straight line. WY is a vertical flagpole. WX and WZ are supporting wires. WX = 18 m, WY = 13 m and angle YWZ = 35°. (a) Calculate WZ Answer .............................................. m [2] (b) Benny said the angle of elevation of W from X is 43.8°. Was Benny correct? Explain your answer Answer [2] W X Y Z 35° 18 m 13 m

3 2 ABC is an equilateral triangle. Angle BDC = 90° , BD = 4.5 cm and BC = 8.7 cm. Calculate (a) the length of DC, Answer DC = ………………….… cm [2] (b) the area of the quadrilateral ABDC. Answer ……………...……………. cm2 [4] A B C D 4.5 cm 8.7 cm

4 3 A, B and C are on level horizontal ground. BC = 78 m, angle ACB = 110° and angle ABC = 26°. C is due north of A. (a) Calculate the bearing of B from C. Answer …………………….……......... [1] (b) Calculate the bearing of A from B. Answer ………………………….…..... [2] (c) Calculate the length of AC. Answer ………………………….……m [3] A B C N 110 ° 26 ° 78 m

5 Extracted from 4NA WA 2023 4 Harry claims that the following three numbers could be the lengths of a right -angled triangle. 55 , 73 , 48 Justify, with clear working, whether his claim is true. Answer ….………………………………………………………………………….. ….………………………………………………………………………….. ….………………………………………………………………………….. ….………………………………………………………………………….. [2] 5 Three points, E, C and G lie on a horizontal field. EC = 900 m, EG = 1082 m, CG = 1255 m, 78CEG =  and the bearing of G from E is 146.