Page 28 - TOP CLASS MATHS T5 KSSM

Mathematics Form 5 Chapter 7 Measures of Dispersion for Grouped Data

(c) Using a scale of 2 cm to 10 g on the horizontal axis and 4. The data below shows the monthly savings, in RM, for a
2 cm to 1 grape on the vertical axis, draw a histogram group of 36 pupils.
for the data. Data di bawah menunjukkan simpanan bulanan, dalam RM,
Menggunakan skala 2 cm kapada 10 g pada paksi bagi sekumpulan 36 murid.
mengufuk dan 2 cm kepada 1 biji anggur pada paksi
mencancang, lukis satu histogram bagi data tersebut. 72 66 67 64 69 61 52 67 67
(d) Based on the histogram drawn in (c), state the number 68 57 72 65 62 59 54 64 47
of grapes with the mass of more than 55 g. 58 73 56 74 63 58 66 69 62
Berdasarkan histogram yang dilukis di (c), nyatakan 64 60 62 55 53 62 57 49 51
bilangan anggur yang jisimnya melebihi 55 g.
(a) Based on the data above, complete the table in the
Answer / Jawapan: answer space.
Berdasarkan data di atas, lengkapkan jadual di ruang
(a) Mass (kg) / Jisim (kg) Frequency / Kekerapan jawapan.
15 – 24 2 (b) Calculate the standard deviation of the data.
25 – 34 5 Hitung sisihan piawai bagi data itu.
(c) Using a scale of 2 cm to RM5 on the horizontal axis and
35 – 44 10
2 cm to 1 pupil on the vertical axis, draw a frequency
45 – 54 8 polygon for the data.
55 – 64 3 Menggunakan skala 2 cm kapada RM5 pada paksi
mengufuk dan 2 cm kepada 1 orang murid pada paksi
65 – 74 2
mencancang, lukis satu poligon kekerapan bagi data
tersebut.
(b) Mass (kg) f x fx fx 2
Jisim (kg) (d) Based on the frequency polygon in (c), state the number
of pupils who saved more than RM60 in a month.
15 – 24 2 19.5 39 760.5 Berdasarkan poligon kekerapan di (c), nyatakan bilangan
25 – 34 5 29.5 147.5 4 351.25 murid yang menyimpan lebih daripada RM60 dalam
35 – 44 10 39.5 395 15 602.5 sebulan.
45 – 54 8 49.5 396 19 602 Answer / Jawapan:
55 – 64 3 59.5 178.5 10 620.75 (a) Savings (RM) Frequency Midpoint
65 – 74 2 69.5 139 9 660.5 Simpanan (RM) Kekerapan Titik tengah

Σf = 30, Σfx = 1 295, Σfx = 60 597.5 41 – 45 0 43
2
60 597.5
1 295


–
σ =  2 46 – 50 2 48
30
30
= 12.512 g 51 – 55 5 53
56 – 60 7 58
(c)
Frequency 61 – 65 10 63
Kekerapan
66 – 70 8 68
10 71 – 75 4 73
76 – 80 0 78
9
8 (b) Savings (RM) f x fx fx 2
Simpanan (RM)
7
46 – 50 2 48 96 4 608
6
51 – 55 5 53 265 14 045
5 56 – 60 7 58 406 23 548
61 – 65 10 63 630 39 690
4
66 – 70 8 68 544 36 992
3
71 – 75 4 73 292 21 316
2
2
Σf = 36, Σfx = 2 233, Σfx = 140 199
1 140 199 2 233 2


–
σ = 
36
0 36
14.5 24.5 34.5 44.5 54.5 64.5 74.5 = RM6.854
Mass (g)/ Jisim (g)
(d) Number of grapes = 3 + 2

Bilangan anggur = 5
© Penerbitan Pelangi Sdn. Bhd. 22