Assignment 6.3
Cumulative Frequency Polygons and Cumulative Frequency Curves
CHAN SUI KI (LA SALLE) COLLEGE
F.2 Mathematics Assignment 6.3
CUMULATIVE FREQUENCY P OLYGONS AND CUMULATIVE FREQUENCY CURVES
Name: ______________________________ Class: _____ Class No.: _____ Date: ________________
1.
Thefollowingfrequencydistributiontableshowstheagesofagroupofstudentsinayouth
centre.
Age
7–8
9–10
11–12
13–14
15–16
17–18
No.ofstudents
12
18
28
15
5
2
a% Completethecumulativefrequencytablefortheabovedata. )6marks+
Agelessthan
6.5
8.5
10.5
10.5
12.5
12.5
14.5
14.5
16.5
16.5
18.5
18.5
Cumulativefrequency
0
12
12
30
30
58
58
73
73
78
78
80
80
b% Constructacumulativefrequencypolygonforthedata. )5marks+
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Assignment 6.3
2.
Cumulative Frequency Polygons and Cumulative Frequency Curves
Thecumulativefrequencycurveshowstheweights,inkg%ofsomestudents.
a% Howmanystudentsarethere? )1mark+
Numberofstudents/40
b% Findthelowerquartile,medianandupperquartile,correcttothenearest0.5kg. )6
marks+
Thecorrespondingcumulativefrequencyofthelower
lowerquartile
lower
/40
40 ×25
25 %
/10
Fromthegraph,lower
lowerquartile/
41.0kg
lower
41.0kg ,cor.tothenearest0.5kg%
Thecorrespondingcumulativefrequencyofthemedian
median
median
/40
40 ×50
50 %
/20
Fromthegraph,median
median/
median 46.0kg
46.0kg ,cor.tothenearest0.5kg%
Thecorrespondingcumulativefrequencyoftheupper
upperquartile
upper
/40
40 ×75
75 %
/30
Fromthegraph,upper
upperquartile/
49.0kg
upper
49.0kg ,cor.tothenearest0.5kg%
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Assignment 6.3
Cumulative Frequency Polygons and Cumulative Frequency Curves
c% Findthe80thpercentile,correcttothenearest0.5kg. )2marks+
Thecorrespondingcumulativefrequencyofthe80
80thpercentile
/40
40 ×80
80 %
/32
Fromthegraph,80
80thpercentile/50.0kg
50.0kg ,cor.tothenearest0.5kg%
Page 8