EduSahara™ Assignment
Name : Mean of Raw Data
Chapter : Statistics
Grade : ICSE Grade VIII
License : Non Commercial Use
Question
1
1.
The scores obtained by 12 students in a test are given below. Find the mean score.
1
13
20
5
19
8
19
7
8
4
7
20
(i)
20
(ii)
1
(iii)
8
(iv)
7
(v)
10
11
12
Question
2
2.
If the mean of
8
1
10
3
x
2
7
4
is
5
1
2
,
find the value of x.
(i)
9
(ii)
10
(iii)
7
(iv)
8
(v)
11
Question
3
3.
The mean of the below random sample is
31
3
10
.
Find the missing quantity.
40
50
36
15
x
27
35
21
26
32
(i)
30
(ii)
29
(iii)
31
(iv)
32
(v)
34
Question
4
4.
Given the mean of
7
samples as
6
3
7
,
what is the mean if a sample value is
increased
by
16
?
(i)
59
7
(ii)
9
(iii)
61
7
(iv)
77
9
Question
5
5.
Given the mean of
6
samples as
13
1
3
,
what is the mean if a sample value is
decreased
by
16
?
(i)
10
(ii)
34
3
(iii)
52
5
(iv)
32
3
(v)
12
Question
6
6.
Given the mean of
10
samples as
6
1
5
,
what is the new mean if two samples
5
and
10
are added ?
(i)
13
2
(ii)
89
14
(iii)
79
12
(iv)
25
4
(v)
77
12
Question
7
7.
Given the mean of
12
samples as
6
1
6
,
what is the new mean if two samples
9
and
5
are removed ?
(i)
3
(ii)
5
(iii)
9
(iv)
6
(v)
7
Question
8
8.
Find the mean of all prime numbers between 20 and 80.
(i)
51
(ii)
54
(iii)
50
(iv)
52
(v)
49
Question
9
9.
Find the mean of all prime numbers between 20 and 60.
(i)
119
3
(ii)
201
5
(iii)
41
(iv)
121
3
Question
10
10.
Find the mean of first 6 multiples of 18.
(i)
61
(ii)
64
(iii)
66
(iv)
63
(v)
62
Question
11
11.
Find the mean of first 5 whole numbers.
(i)
0
(ii)
3
(iii)
2
(iv)
1
(v)
4
Question
12
12.
Find the mean of first 6 multiples of 7.
(i)
49
2
(ii)
25
(iii)
97
4
(iv)
47
2
(v)
51
2
Question
13
13.
Find the mean of the first 20 odd numbers.
(i)
19
(ii)
21
(iii)
17
(iv)
23
(v)
20
Question
14
14.
Find the mean of the first 20 even numbers.
(i)
21
(ii)
20
(iii)
19
(iv)
23
(v)
22
Question
15
15.
The marks obtained by 14 students in a test are given below. Find their mean marks.
47
21
28
22
42
23
14
19
2
39
3
18
50
16
(i)
220
9
(ii)
172
7
(iii)
170
7
(iv)
174
7
(v)
124
5
Question
16
16.
The marks obtained by 10 students in a test are given below. Find the mean of their marks when the marks of each student is increased by 4.
50
42
16
38
6
13
7
24
37
4
(i)
55
2
(ii)
277
10
(iii)
223
8
(iv)
279
10
(v)
331
12
Question
17
17.
The marks obtained by 15 students in a test are given below. Find the mean of their marks when the marks of each student is decreased by 5.
30
13
44
33
46
18
2
26
40
22
33
1
10
23
29
(i)
61
3
(ii)
19
(iii)
21
(iv)
59
3
(v)
97
5
Question
18
18.
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 doubled.
29
30
35
39
39
42
4
7
10
28
19
27
(i)
52
(ii)
103
2
(iii)
205
4
(iv)
105
2
(v)
101
2
Question
19
19.
Heights of 14 students (in cm) are given below. Find the mean height.
142
148
175
155
148
134
166
136
158
126
153
143
159
134
(i)
2105
14
cm
(ii)
2091
14
cm
(iii)
297
2
cm
(iv)
1039
7
cm
(v)
2077
14
cm
Question
20
20.
Heights of 10 plants (in cm) are given below. Find the mean height.
71
51
86
98
93
55
92
51
97
90
(i)
397
5
cm
(ii)
394
5
cm
(iii)
393
5
cm
(iv)
402
5
cm
(v)
392
5
cm
Question
21
21.
Ages of 11 students (in years) are given below. Find the mean age.
12
15
13
10
12
14
13
15
12
10
14
(i)
162
11
years
(ii)
142
11
years
(iii)
141
11
years
(iv)
140
11
years
(v)
151
11
years
Question
22
22.
Rainfall of 10 days (in mm) are given below. Find the mean rainfall.
5
8
5
13
14
8
15
6
6
5
(i)
9
mm
(ii)
17
2
mm
(iii)
19
2
mm
(iv)
21
2
mm
Question
23
23.
Scores of 15 students are given below. Find the mean score.
90
74
90
74
70
71
70
73
88
76
80
73
80
75
90
(i)
1189
15
(ii)
1174
15
(iii)
235
3
(iv)
1204
15
(v)
392
5
Question
24
24.
Temperatures of 11 days (in °C) are given below. Find the mean temperature.
29
26
26
27
32
31
26
35
28
30
29
(i)
28
°C
(ii)
29
°C
(iii)
31
°C
(iv)
30
°C
(v)
27
°C
Question
25
25.
Weights of 10 students (in kg) are given below. Find the mean weight.
53
58
45
49
53
49
60
51
41
52
(i)
521
10
kg
(ii)
513
10
kg
(iii)
511
10
kg
(iv)
256
5
kg
(v)
531
10
kg
Question
26
26.
Daily wages of 15 labourers (in ₹) are given below. Find the mean wage.
466
341
358
419
397
364
485
376
473
485
307
352
492
416
315
(i)
₹
405.07
(ii)
₹
403.20
(iii)
₹
404.07
(iv)
₹
403.07
(v)
₹
403.13
Question
27
27.
The arithmetic mean of
47
28
42
6
6
9
is
(i)
22
(ii)
21
(iii)
25
(iv)
24
(v)
23
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
7
samples is
27
2
7
,
what is the new mean if
8
is added to each number.
(i)
249
7
(ii)
177
5
(iii)
317
9
(iv)
35
(v)
247
7
Question
30
30.
If the mean of
4
samples is
24
3
4
,
what is the new mean if
8
is subtracted from each number.
(i)
67
4
(ii)
35
2
(iii)
65
4
(iv)
33
2
(v)
69
4
Question
31
31.
If the mean of
4
samples is
24
,
what is the new mean if each number is multiplied by
3
.
(i)
72
(ii)
71
(iii)
69
(iv)
75
(v)
73
Question
32
32.
The mean of
10
numbers is
14
.
Upon
excluding
one number,
the mean becomes
13
2
3
.
Find the
excluded
number.
(i)
17
(ii)
14
(iii)
19
(iv)
16
(v)
18
Question
33
33.
The mean of
9
numbers is
8
1
9
.
Upon
adding
one number,
the mean becomes
8
1
5
.
Find the
included
number.
(i)
6
(ii)
10
(iii)
9
(iv)
12
(v)
8
Assignment Key
1) (v)
2) (i)
3) (iii)
4) (iii)
5) (iv)
6) (v)
7) (iv)
8) (i)
9) (iv)
10) (iv)
11) (iii)
12) (i)
13) (v)
14) (i)
15) (ii)
16) (ii)
17) (iv)
18) (ii)
19) (v)
20) (v)
21) (iv)
22) (ii)
23) (ii)
24) (ii)
25) (iii)
26) (iv)
27) (v)
28) (iv)
29) (v)
30) (i)
31) (i)
32) (i)
33) (iii)
