Page 19 - TOP CLASS MATHS T5 KSSM

Mathematics Form 5 Chapter 7 Measures of Dispersion for Grouped Data

(a) Height (cm) Frequency Cumulative frequency
Kekerapan longgokan
Tinggi (cm) Kekerapan
151 – 155 5 40
156 – 160 8
30
161 – 165 16
20
166 – 170 9
171 – 175 2 10
0
171 + 175 151 + 155 150.5 155.5 160.5 165.5 170.5 175.5
Range / Julat = – Height (cm)
2 2 Tinggi (cm)
= 173 – 153
= 20 cm
From the ogive, / Daripada ogif, From the ogive, / Daripada ogif,
1 3
position of Q 1 / kedudukan Q 1: × 40 = 10 position of Q 3 / kedudukan Q 3: × 40 = 30
4 4
Interquartile range/ Julat antara kuartil = 166.0 − 159.0 = 7 cm
(b) Price (RM) Frequency
Harga (RM) Kekerapan Cumulative frequency
Kekerapan longgokan
15 – 19 2
40
20 – 24 7
25 – 29 15 30
30 – 34 12 20
35 – 39 3
10
35 + 39 15 + 19 0
Range / Julat = – 14.5 19.5 24.5 29.5 34.5 39.5
2 2 Price(RM)
= 37 – 17 Harga (RM)
= RM20
From the ogive, / Daripada ogif, From the ogive, / Daripada ogif,
1 3
position of Q 1 / kedudukan Q 1: × 39 = 9.75  10 position of Q 3 / kedudukan Q 3: × 39 = 29.25  29
4 4
Interquartile range/ Julat antara kuartil = 31.0 − 25.0 = RM6
(c) Marks Frequency Cumulative frequency
Markah Kekerapan Kekerapan longgokan
1 – 10 5
60
11 – 20 8
21 – 30 17 40
31 – 40 14 20
41 – 50 11
0
51 – 60 6 0.5 10.5 20.5 30.5 40.5 50.5 60.5
Marks
Markah
51 + 60 1 + 10
Range / Julat = –
2 2
= 55.5 − 5.5
= 50

From the ogive, / Daripada ogif, From the ogive, / Daripada ogif,
1 3
position of Q 1 / kedudukan Q 1: × 61 = 15.25  15 position of Q 3 / kedudukan Q 3: × 61 = 45.75  46
4 4
Interquartile range/ Julat antara kuartil = 41.5 − 21.5 = 20

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