EduSahara™ Assignment
Name : Arithmetic Mean
Chapter : Frequency Distribution Tables and Graphs
Grade : SSC Grade VIII
License : Non Commercial Use
Question
1
1.
If the mean of
3
10
9
x
6
5
1
is
5
6
7
,
find the value of x.
(i)
5
(ii)
6
(iii)
8
(iv)
10
(v)
7
Question
2
2.
The mean of the below random sample is
27
1
10
.
Find the missing quantity.
20
34
26
27
13
x
15
10
44
49
(i)
34
(ii)
33
(iii)
30
(iv)
32
(v)
36
Question
3
3.
Given the mean of
11
samples as
12
5
11
,
what is the mean if a sample value is
increased
by
13
?
(i)
152
11
(ii)
150
11
(iii)
124
9
(iv)
176
13
(v)
148
11
Question
4
4.
Given the mean of
14
samples as
9
13
14
,
what is the mean if a sample value is
decreased
by
20
?
(i)
15
2
(ii)
9
(iii)
17
2
(iv)
33
4
(v)
19
2
Question
5
5.
Given the mean of
10
samples as
6
3
10
,
what is the new mean if two samples
6
and
6
are added ?
(i)
27
4
(ii)
13
2
(iii)
23
4
(iv)
37
6
(v)
25
4
Question
6
6.
Given the mean of
12
samples as
4
1
3
,
what is the new mean if two samples
6
and
5
are removed ?
(i)
41
10
(ii)
39
10
(iii)
43
10
(iv)
33
8
(v)
49
12
Question
7
7.
Find the mean of all prime numbers between 20 and 70.
(i)
491
11
(ii)
403
9
(iii)
493
11
(iv)
579
13
(v)
489
11
Question
8
8.
Find the mean of all prime numbers between 40 and 90.
(i)
509
8
(ii)
257
4
(iii)
385
6
(iv)
127
2
(v)
383
6
Question
9
9.
Find the mean of first 8 multiples of 13.
(i)
59
(ii)
115
2
(iii)
117
2
(iv)
233
4
(v)
119
2
Question
10
10.
Find the mean of first 9 whole numbers.
(i)
3
(ii)
5
(iii)
4
(iv)
6
(v)
1
Question
11
11.
Find the mean of first 10 multiples of 14.
(i)
76
(ii)
75
(iii)
79
(iv)
77
(v)
78
Question
12
12.
Find the mean of the first 10 odd numbers.
(i)
11
(ii)
12
(iii)
8
(iv)
10
(v)
9
Question
13
13.
Find the mean of the first 10 even numbers.
(i)
11
(ii)
10
(iii)
8
(iv)
12
(v)
13
Question
14
14.
The marks obtained by 13 students in a test are given below. Find their mean marks.
31
30
46
31
25
46
15
16
37
11
36
13
32
(i)
369
13
(ii)
371
13
(iii)
85
3
(iv)
367
13
(v)
313
11
Question
15
15.
The marks obtained by 11 students in a test are given below. Find the mean of their marks when the marks of each student is increased by 4.
12
45
46
42
22
50
7
32
12
30
46
(i)
386
11
(ii)
390
11
(iii)
458
13
(iv)
106
3
(v)
388
11
Question
16
16.
The marks obtained by 14 students in a test are given below. Find the mean of their marks when the marks of each student is decreased by 2.
43
30
31
6
50
21
38
36
22
13
15
43
8
37
(i)
363
14
(ii)
365
14
(iii)
367
14
(iv)
313
12
(v)
417
16
Question
17
17.
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 doubled.
10
21
14
26
36
11
22
45
45
40
(i)
53
(ii)
54
(iii)
57
(iv)
55
(v)
52
Question
18
18.
Heights of 13 students (in cm) are given below. Find the mean height.
160
157
174
135
146
135
149
168
172
148
174
134
141
(i)
1993
13
cm
(ii)
1995
13
cm
(iii)
1994
13
cm
(iv)
2006
13
cm
(v)
2019
13
cm
Question
19
19.
Heights of 13 plants (in cm) are given below. Find the mean height.
67
72
89
100
58
50
64
75
76
77
58
82
50
(i)
944
13
cm
(ii)
920
13
cm
(iii)
919
13
cm
(iv)
931
13
cm
(v)
918
13
cm
Question
20
20.
Ages of 15 students (in years) are given below. Find the mean age.
12
14
15
14
11
11
10
12
11
12
14
14
12
11
10
(i)
61
5
years
(ii)
63
5
years
(iii)
71
5
years
(iv)
66
5
years
(v)
62
5
years
Question
21
21.
Rainfall of 12 days (in mm) are given below. Find the mean rainfall.
9
10
5
10
8
7
8
10
6
13
5
12
(i)
35
4
mm
(ii)
127
12
mm
(iii)
115
12
mm
(iv)
26
3
mm
(v)
103
12
mm
Question
22
22.
Scores of 10 students are given below. Find the mean score.
74
85
75
86
80
77
78
78
90
86
(i)
809
10
(ii)
811
10
(iii)
829
10
(iv)
81
(v)
819
10
Question
23
23.
Temperatures of 15 days (in °C) are given below. Find the mean temperature.
34
35
27
30
35
27
27
27
35
35
25
26
31
28
25
(i)
151
5
°C
(ii)
149
5
°C
(iii)
159
5
°C
(iv)
30
°C
(v)
154
5
°C
Question
24
24.
Weights of 12 students (in kg) are given below. Find the mean weight.
41
59
46
47
49
45
41
57
45
53
54
47
(i)
152
3
kg
(ii)
49
kg
(iii)
149
3
kg
(iv)
148
3
kg
(v)
146
3
kg
Question
25
25.
Daily wages of 13 labourers (in ₹) are given below. Find the mean wage.
491
336
498
419
310
487
462
474
357
361
321
419
405
(i)
₹
411.77
(ii)
₹
410.85
(iii)
₹
410.77
(iv)
₹
410.92
(v)
₹
412.77
Question
26
26.
If the mean of
4
samples is
7
1
2
,
what is the new mean if
8
is added to each number.
(i)
33
2
(ii)
29
2
(iii)
61
4
(iv)
31
2
(v)
16
Question
27
27.
If the mean of
4
samples is
27
,
what is the new mean if
4
is subtracted from each number.
(i)
25
(ii)
21
(iii)
22
(iv)
23
(v)
24
Question
28
28.
If the mean of
8
samples is
26
7
8
,
what is the new mean if each number is multiplied by
4
.
(i)
215
2
(ii)
213
2
(iii)
429
4
(iv)
108
(v)
217
2
Question
29
29.
The mean of
8
numbers is
16
1
8
.
Upon
excluding
one number,
the mean becomes
16
1
7
.
Find the
excluded
number.
(i)
16
(ii)
19
(iii)
17
(iv)
14
(v)
15
Question
30
30.
The mean of
7
numbers is
10
5
7
.
Upon
adding
one number,
the mean becomes
10
5
8
.
Find the
included
number.
(i)
13
(ii)
9
(iii)
8
(iv)
10
(v)
11
Question
31
31.
The scores obtained by 12 students in a test are given below. Find the mean score.
9
17
6
20
11
12
5
8
4
11
10
3
(i)
9
2
3
(ii)
9
1
2
(iii)
3
(iv)
11
(v)
17
Question
32
32.
The arithmetic mean of a + 2, a, and a - 2 is
(i)
a
(ii)
a - 2
(iii)
3a
(iv)
a + 2
Question
33
33.
The arithmetic mean of
24
43
36
42
40
28
33
26
is
(i)
35
(ii)
34
(iii)
33
(iv)
32
(v)
36
Assignment Key
1) (v)
2) (ii)
3) (ii)
4) (iii)
5) (v)
6) (i)
7) (i)
8) (v)
9) (iii)
10) (iii)
11) (iv)
12) (iv)
13) (i)
14) (i)
15) (v)
16) (ii)
17) (ii)
18) (i)
19) (v)
20) (i)
21) (v)
22) (i)
23) (ii)
24) (v)
25) (iii)
26) (iv)
27) (iv)
28) (i)
29) (i)
30) (iv)
31) (i)
32) (i)
33) (ii)
