Teacher's Guide - Pearson

Assessment 4Question 11.1 a) Two widths 5 2a and length 5 b; fourth side of pen is formed by the river. ü(1)b) b 5 100 2 2a ü A 5 a(100 2 2a) ü(2)c) a(100 2 2a) 5 800 ü 2a 2 2 100a 1 800 5 0 ü a 5 40 (not applicable) ü or a 5 10 ü So a 5 10 and b 5 80 ü(5)d) Dimensions: 80 metres long, 10 metres wide. üü(2)1.2 a) (x 2 5)(x 1 1) 5 0 ü x 5 5 ü or x 5 21 ü(3)b) x 5 5 metres is where the water jet hits the ground. üü(2)c) 5 m üü(2)d) 2 m üü(2)e) 9 m (substitute x 5 2 into y 5 2x 2 1 4x 1 y) ü(1) [20]Question 22.1 a) 26,7 kg üü(2)b) Q 15 30 kg üü; Q 35 22 kg üü(4)c) 3 rd : 14.5 kg üü; 10 th : 18 kg üü: 80 th : 31.5 kg üü(6)d) 75 lambs are below 37 kg. üü(2)e) 15 heaviest lambs: 32 2 40 kg üü(2)2.2 a)Classes Frequency (f) Class midpoints (x) f 3 x10 < x < 15 3 12.5 37.515 < x < 20 11 17.5 192.520 < x < 25 17 22.5 382.525 < x < 30 28 27.5 770.030 < x < 35 12 32.5 390.035 < x < 40 9 37.5 337.5üüf 5 n 5 80 üfx 5 2 110 ü(4)b) Model class: 25 < x < 30 üü(2)c) Median class: 25 < x < 30 üü(2)d) Estimated mean = ___ fxn ​2 110= ​ _____80 ​ ü= 26.375 ü(2)Chapter 23: Research skills: Data analysis and interpretation143