EduSahara™ Assignment
Name : Mean of Raw Data
Chapter : Statistics
Grade : ICSE Grade VIII
License : Non Commercial Use
Question
1
1.
The scores obtained by 9 students in a test are given below. Find the mean score.
1
11
17
16
14
19
8
12
9
(i)
12
(ii)
1
(iii)
19
(iv)
18
(v)
11
8
9
Question
2
2.
If the mean of
5
2
7
10
x
9
4
6
is
5
3
4
,
find the value of x.
(i)
3
(ii)
5
(iii)
2
(iv)
4
(v)
0
Question
3
3.
The mean of the below random sample is
25
3
5
.
Find the missing quantity.
18
35
34
18
x
18
27
15
44
24
(i)
25
(ii)
24
(iii)
23
(iv)
22
(v)
20
Question
4
4.
Given the mean of
12
samples as
13
1
4
,
what is the mean if a sample value is
increased
by
19
?
(i)
91
6
(ii)
89
6
(iii)
117
8
(iv)
61
4
(v)
29
2
Question
5
5.
Given the mean of
10
samples as
9
3
5
,
what is the mean if a sample value is
decreased
by
19
?
(i)
15
2
(ii)
79
10
(iii)
91
12
(iv)
63
8
(v)
77
10
Question
6
6.
Given the mean of
10
samples as
5
,
what is the new mean if two samples
10
and
2
are added ?
(i)
29
6
(ii)
31
6
(iii)
21
4
(iv)
41
8
(v)
11
2
Question
7
7.
Given the mean of
12
samples as
4
7
12
,
what is the new mean if two samples
2
and
2
are removed ?
(i)
53
10
(ii)
51
10
(iii)
61
12
(iv)
49
10
(v)
41
8
Question
8
8.
Find the mean of all prime numbers between 50 and 90.
(i)
637
9
(ii)
495
7
(iii)
775
11
(iv)
635
9
(v)
211
3
Question
9
9.
Find the mean of all prime numbers between 10 and 80.
(i)
43
(ii)
42
(iii)
45
(iv)
40
(v)
44
Question
10
10.
Find the mean of first 8 multiples of 17.
(i)
155
2
(ii)
77
(iii)
151
2
(iv)
305
4
(v)
153
2
Question
11
11.
Find the mean of first 5 whole numbers.
(i)
0
(ii)
1
(iii)
5
(iv)
2
(v)
3
Question
12
12.
Find the mean of first 9 multiples of 18.
(i)
88
(ii)
89
(iii)
91
(iv)
90
(v)
93
Question
13
13.
Find the mean of the first 20 odd numbers.
(i)
19
(ii)
21
(iii)
22
(iv)
17
(v)
20
Question
14
14.
Find the mean of the first 10 even numbers.
(i)
11
(ii)
10
(iii)
9
(iv)
13
(v)
12
Question
15
15.
The marks obtained by 10 students in a test are given below. Find their mean marks.
44
22
21
34
49
49
39
46
4
9
(i)
317
10
(ii)
63
2
(iii)
379
12
(iv)
319
10
(v)
255
8
Question
16
16.
The marks obtained by 12 students in a test are given below. Find the mean of their marks when the marks of each student is increased by 5.
41
5
14
20
12
32
27
45
14
15
47
7
(i)
113
4
(ii)
111
4
(iii)
57
2
(iv)
115
4
(v)
169
6
Question
17
17.
The marks obtained by 12 students in a test are given below. Find the mean of their marks when the marks of each student is decreased by 9.
7
17
26
44
3
8
3
30
40
32
5
19
(i)
21
2
(ii)
41
4
(iii)
11
(iv)
23
2
(v)
19
2
Question
18
18.
The marks obtained by 13 students in a test are given below. Find the mean of their marks when the marks of each student is doubled.
25
34
50
16
33
35
27
38
41
29
33
6
25
(i)
782
13
(ii)
784
13
(iii)
904
15
(iv)
786
13
(v)
664
11
Question
19
19.
Heights of 12 students (in cm) are given below. Find the mean height.
135
160
156
148
135
175
142
140
144
170
150
174
(i)
1831
12
cm
(ii)
1841
12
cm
(iii)
305
2
cm
(iv)
1853
12
cm
(v)
1829
12
cm
Question
20
20.
Heights of 13 plants (in cm) are given below. Find the mean height.
71
71
50
68
69
85
52
96
90
85
58
66
54
(i)
916
13
cm
(ii)
917
13
cm
(iii)
915
13
cm
(iv)
928
13
cm
(v)
941
13
cm
Question
21
21.
Ages of 11 students (in years) are given below. Find the mean age.
11
14
13
15
11
11
14
10
10
13
13
(i)
135
11
years
(ii)
137
11
years
(iii)
136
11
years
(iv)
157
11
years
(v)
146
11
years
Question
22
22.
Rainfall of 15 days (in mm) are given below. Find the mean rainfall.
12
11
5
8
6
8
15
15
7
5
6
14
7
5
12
(i)
151
15
mm
(ii)
46
5
mm
(iii)
137
15
mm
(iv)
166
15
mm
(v)
136
15
mm
Question
23
23.
Scores of 11 students are given below. Find the mean score.
73
79
86
83
89
87
71
78
76
70
88
(i)
78
(ii)
79
(iii)
81
(iv)
82
(v)
80
Question
24
24.
Temperatures of 14 days (in °C) are given below. Find the mean temperature.
32
33
31
33
35
32
28
31
25
29
26
33
27
28
(i)
437
14
°C
(ii)
425
14
°C
(iii)
212
7
°C
(iv)
423
14
°C
(v)
451
14
°C
Question
25
25.
Weights of 14 students (in kg) are given below. Find the mean weight.
48
42
58
52
58
40
47
53
49
56
50
46
40
43
(i)
342
7
kg
(ii)
49
kg
(iii)
341
7
kg
(iv)
348
7
kg
(v)
355
7
kg
Question
26
26.
Daily wages of 10 labourers (in ₹) are given below. Find the mean wage.
400
380
422
300
352
426
340
376
417
408
(i)
₹
382.10
(ii)
₹
384.10
(iii)
₹
382.20
(iv)
₹
383.10
(v)
₹
382.30
Question
27
27.
The arithmetic mean of
10
20
12
29
27
1
is
(i)
17.5
(ii)
16.5
(iii)
18.5
(iv)
14.5
(v)
15.5
Question
28
28.
The arithmetic mean of a + 2, a, and a - 2 is
(i)
a + 2
(ii)
3a
(iii)
a - 2
(iv)
a
Question
29
29.
If the mean of
8
samples is
31
3
8
,
what is the new mean if
5
is added to each number.
(i)
289
8
(ii)
73
2
(iii)
293
8
(iv)
363
10
(v)
291
8
Question
30
30.
If the mean of
8
samples is
22
7
8
,
what is the new mean if
5
is subtracted from each number.
(i)
145
8
(ii)
109
6
(iii)
143
8
(iv)
141
8
(v)
177
10
Question
31
31.
If the mean of
5
samples is
21
2
5
,
what is the new mean if each number is multiplied by
6
.
(i)
128
(ii)
898
7
(iii)
642
5
(iv)
386
3
(v)
644
5
Question
32
32.
The mean of
7
numbers is
11
5
7
.
Upon
excluding
one number,
the mean becomes
13
1
3
.
Find the
excluded
number.
(i)
2
(ii)
5
(iii)
3
(iv)
1
(v)
0
Question
33
33.
The mean of
10
numbers is
10
4
5
.
Upon
adding
one number,
the mean becomes
9
10
11
.
Find the
included
number.
(i)
0
(ii)
1
(iii)
-2
(iv)
2
(v)
3
Assignment Key
1) (v)
2) (i)
3) (iii)
4) (ii)
5) (v)
6) (ii)
7) (ii)
8) (iv)
9) (i)
10) (v)
11) (iv)
12) (iv)
13) (v)
14) (i)
15) (i)
16) (i)
17) (i)
18) (ii)
19) (v)
20) (iii)
21) (i)
22) (v)
23) (v)
24) (iv)
25) (iii)
26) (i)
27) (ii)
28) (iv)
29) (v)
30) (iii)
31) (iii)
32) (i)
33) (ii)
