Page 9 - TOP CLASS MATHS T5 KSSM

Mathematics Form 5 Chapter 7 Measures of Dispersion for Grouped Data
3. Determine the lower limit, upper limit, midpoint, lower boundary, upper boundary and size of class interval
for each of the class intervals in the following table. PL 2
Tentukan had bawah, had atas, titik tengah, sempadan bawah, sempadan atas dan saiz selang kelas bagi setiap selang kelas dalam
jadual berikut.
Class interval Example
Selang kelas
51 – 60 (a) 40 – 47 (b) 125 – 140 (c) 230 – 250 (d) 6.1 – 6.9

Lower limit
Had bawah 51 40 125 230 6.1

Upper limit 60 47 140 250 6.9
Had atas

Midpoint 51 + 60 40 + 47 125 + 140 230 + 250 6.1 + 6.9
Titik tengah 2 2 2 2 2
= 55.5 = 43.5 = 132.5 = 240 = 6.5

Lower boundary 50 + 51 39 + 40 124 + 125 229 + 230 6.0 + 6.1
Sempadan bawah 2 2 2 2 2
= 50.5 = 39.5 = 124.5 = 229.5 = 6.05

Upper boundary 60 + 61 47 + 48 140 + 141 250 + 251 6.9 + 7.0
Sempadan atas 2 2 2 2 2
= 60.5 = 47.5 = 140.5 = 250.5 = 6.95

Size of class 60.5 – 50.5 47.5 – 39.5 140.5 – 124.5 250.5 – 229.5 6.95 – 6.05
interval = 10 = 8 = 16 = 21 = 0.9
Saiz selang kelas

4. Complete the column of cumulative frequency for each of the following frequency tables. PL 2
Lengkapkan lajur kekerapan longgokan bagi setiap jadual kekerapan berikut.
Example
Mass (kg) Frequency Cumulative frequency
Jisim (kg) Kekerapan Kekerapan longgokan
41 – 45 4 4 Frequency Cumulative frequency
Kekerapan Kekerapan longgokan
46 – 50 9 + 9 13 4 4
51 – 55 12 + 12 25 9 + 13
+
56 – 60 10 + 10 35 12 + 25
10
35
61 – 65 7 + 7 42 7 + 42
This number must be the same with the total frequency.
Nombor ini mesti sama dengan jumlah kekerapan.
Total frequency = 4 + 9 + 12 + 10 + 7
Jumlah kekerapan
= 42

(a) Height (cm) Frequency Cumulative frequency
Tinggi (cm) Kekerapan Kekerapan longgokan
150 – 154 2 2
+
155 – 159 11 13
+
160 – 164 25 38
+
165 – 169 18 56
+
170 – 174 9 65

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