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
7
3
x
6
8
is
5
3
5
,
find the value of x.
(i)
6
(ii)
3
(iii)
1
(iv)
5
(v)
4
Question
2
2.
The mean of the below random sample is
28
7
10
.
Find the missing quantity.
44
34
31
18
46
x
20
27
31
19
(i)
14
(ii)
17
(iii)
20
(iv)
16
(v)
18
Question
3
3.
Given the mean of
14
samples as
9
1
14
,
what is the mean if a sample value is
increased
by
11
?
(i)
67
7
(ii)
69
7
(iii)
29
3
(iv)
71
7
(v)
51
5
Question
4
4.
Given the mean of
12
samples as
9
3
4
,
what is the mean if a sample value is
decreased
by
13
?
(i)
42
5
(ii)
8
(iii)
28
3
(iv)
26
3
(v)
10
Question
5
5.
Given the mean of
10
samples as
4
4
5
,
what is the new mean if two samples
3
and
6
are added ?
(i)
19
4
(ii)
11
2
(iii)
21
4
(iv)
9
2
(v)
17
4
Question
6
6.
Given the mean of
12
samples as
6
2
3
,
what is the new mean if two samples
10
and
7
are removed ?
(i)
25
4
(ii)
61
10
(iii)
13
2
(iv)
63
10
(v)
51
8
Question
7
7.
Find the mean of all prime numbers between 40 and 90.
(i)
385
6
(ii)
383
6
(iii)
509
8
(iv)
257
4
(v)
127
2
Question
8
8.
Find the mean of all prime numbers between 30 and 70.
(i)
439
9
(ii)
437
9
(iii)
49
(iv)
535
11
Question
9
9.
Find the mean of first 7 multiples of 17.
(i)
67
(ii)
69
(iii)
65
(iv)
68
(v)
70
Question
10
10.
Find the mean of first 10 whole numbers.
(i)
9
2
(ii)
5
(iii)
11
2
(iv)
7
2
(v)
17
4
Question
11
11.
Find the mean of first 8 multiples of 6.
(i)
28
(ii)
30
(iii)
27
(iv)
24
(v)
26
Question
12
12.
Find the mean of the first 20 odd numbers.
(i)
20
(ii)
22
(iii)
18
(iv)
19
(v)
21
Question
13
13.
Find the mean of the first 10 even numbers.
(i)
11
(ii)
8
(iii)
12
(iv)
14
(v)
10
Question
14
14.
The marks obtained by 13 students in a test are given below. Find their mean marks.
2
3
49
30
9
30
15
6
42
42
25
14
39
(i)
260
11
(ii)
304
13
(iii)
352
15
(iv)
306
13
(v)
308
13
Question
15
15.
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 increased by 3.
5
20
39
24
15
24
3
43
50
16
11
14
42
29
10
(i)
28
(ii)
27
(iii)
26
(iv)
23
(v)
25
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 4.
30
38
37
1
17
34
28
34
23
37
3
7
15
49
(i)
339
16
(ii)
297
14
(iii)
295
14
(iv)
299
14
(v)
85
4
Question
17
17.
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 doubled.
35
40
6
45
9
13
38
3
28
3
47
(i)
630
13
(ii)
532
11
(iii)
146
3
(iv)
534
11
(v)
536
11
Question
18
18.
Heights of 12 students (in cm) are given below. Find the mean height.
161
149
159
152
148
160
133
139
152
169
133
147
(i)
907
6
cm
(ii)
913
6
cm
(iii)
451
3
cm
(iv)
301
2
cm
(v)
901
6
cm
Question
19
19.
Heights of 10 plants (in cm) are given below. Find the mean height.
96
51
72
54
98
66
51
100
82
82
(i)
378
5
cm
(ii)
381
5
cm
(iii)
377
5
cm
(iv)
376
5
cm
(v)
386
5
cm
Question
20
20.
Ages of 13 students (in years) are given below. Find the mean age.
15
14
14
14
10
10
15
14
12
10
11
13
12
(i)
190
13
years
(ii)
177
13
years
(iii)
166
13
years
(iv)
165
13
years
(v)
164
13
years
Question
21
21.
Rainfall of 11 days (in mm) are given below. Find the mean rainfall.
14
6
5
13
12
6
6
8
13
9
8
(i)
111
11
mm
(ii)
101
11
mm
(iii)
122
11
mm
(iv)
102
11
mm
(v)
100
11
mm
Question
22
22.
Scores of 15 students are given below. Find the mean score.
71
76
71
86
82
77
82
80
83
70
83
80
77
70
81
(i)
1169
15
(ii)
1184
15
(iii)
1171
15
(iv)
1199
15
(v)
78
Question
23
23.
Temperatures of 11 days (in °C) are given below. Find the mean temperature.
29
28
26
30
30
28
28
25
29
29
28
(i)
310
11
°C
(ii)
321
11
°C
(iii)
311
11
°C
(iv)
332
11
°C
(v)
312
11
°C
Question
24
24.
Weights of 14 students (in kg) are given below. Find the mean weight.
50
46
55
57
58
43
58
56
52
51
45
45
44
47
(i)
105
2
kg
(ii)
51
kg
(iii)
101
2
kg
(iv)
103
2
kg
Question
25
25.
Daily wages of 13 labourers (in ₹) are given below. Find the mean wage.
457
377
388
461
370
348
383
410
462
360
437
421
476
(i)
₹
411.54
(ii)
₹
412.54
(iii)
₹
411.69
(iv)
₹
413.54
(v)
₹
411.62
Question
26
26.
If the mean of
4
samples is
22
,
what is the new mean if
9
is added to each number.
(i)
34
(ii)
28
(iii)
31
(iv)
30
(v)
32
Question
27
27.
If the mean of
4
samples is
21
1
4
,
what is the new mean if
6
is subtracted from each number.
(i)
31
2
(ii)
59
4
(iii)
63
4
(iv)
91
6
(v)
61
4
Question
28
28.
If the mean of
7
samples is
29
2
7
,
what is the new mean if each number is multiplied by
3
.
(i)
441
5
(ii)
263
3
(iii)
613
7
(iv)
617
7
(v)
615
7
Question
29
29.
The mean of
8
numbers is
8
1
2
.
Upon
excluding
one number,
the mean becomes
9
.
Find the
excluded
number.
(i)
6
(ii)
3
(iii)
5
(iv)
8
(v)
4
Question
30
30.
The mean of
5
numbers is
11
3
5
.
Upon
adding
one number,
the mean becomes
12
2
3
.
Find the
included
number.
(i)
21
(ii)
16
(iii)
18
(iv)
19
(v)
17
Question
31
31.
The scores obtained by 9 students in a test are given below. Find the mean score.
9
10
2
2
18
13
17
9
13
(i)
10
(ii)
16
(iii)
10
1
3
(iv)
2
(v)
18
Question
32
32.
The arithmetic mean of a + 2, a, and a - 2 is
(i)
3a
(ii)
a
(iii)
a - 2
(iv)
a + 2
Question
33
33.
The arithmetic mean of
2
47
46
10
12
is
(i)
22.4
(ii)
23.4
(iii)
24.4
(iv)
25.4
(v)
21.4
Assignment Key
1) (v)
2) (ii)
3) (ii)
4) (iv)
5) (i)
6) (iv)
7) (ii)
8) (i)
9) (iv)
10) (i)
11) (iii)
12) (i)
13) (i)
14) (iv)
15) (iii)
16) (ii)
17) (iv)
18) (v)
19) (iv)
20) (v)
21) (v)
22) (i)
23) (i)
24) (iii)
25) (i)
26) (iii)
27) (v)
28) (v)
29) (iii)
30) (iii)
31) (iii)
32) (ii)
33) (ii)
