EduSahara™ Worksheet

Question 1

1.

The scores obtained by 12 students in a test are given below. Find the mean score.
20

17

13

10

6

9

20

15

11

5

9

13

(i)

12

1
3
(ii)

15
(iii)

5
(iv)

9
(v)

20

Question 2

2.

(i)

10
(ii)

6
(iii)

8
(iv)

9
(v)

7

Question 3

3.

(i)

14
(ii)

66
5
(iii)

38
3
(iv)

40
3

Question 4

4.

(i)

101
12
(ii)

17
2
(iii)

103
12
(iv)

33
4
(v)

117
14

Question 5

5.

Given the mean of
10
samples as
6

2
5
,

what is the new mean if two samples
7
and
4
are added ?

(i)

13
2
(ii)

25
4
(iii)

37
6
(iv)

23
4
(v)

27
4

Question 6

6.

Given the mean of
12
samples as
5

7
12
,

what is the new mean if two samples
9
and
6
are removed ?

(i)

24
5
(ii)

28
5
(iii)

36
7
(iv)

16
3
(v)

26
5

Question 7

7.

Find the mean of all prime numbers between 50 and 70.

(i)

60
(ii)

59
(iii)

61
(iv)

62
(v)

57

Question 8

8.

Find the mean of all prime numbers between 30 and 100.

(i)

311
5
(ii)

931
15
(iii)

807
13
(iv)

1055
17
(v)

929
15

Question 9

9.

Find the mean of first 9 multiples of 15.

(i)

75
(ii)

73
(iii)

77
(iv)

74
(v)

76

Question 10

10.

Find the mean of first 6 whole numbers.

(i)

9
4
(ii)

7
2
(iii)

5
2
(iv)

3
(v)

3
2

Question 11

11.

Find the mean of first 8 multiples of 9.

(i)

81
2
(ii)

41
(iii)

161
4
(iv)

83
2
(v)

79
2

Question 12

12.

Find the mean of the first 20 odd numbers.

(i)

19
(ii)

18
(iii)

20
(iv)

21
(v)

23

Question 13

13.

Find the mean of the first 15 even numbers.

(i)

16
(ii)

19
(iii)

13
(iv)

15
(v)

17

Question 14

14.

The marks obtained by 14 students in a test are given below. Find their mean marks.

15

18

36

36

26

31

6

20

37

37

32

16

31

46

(i)

55
2
(ii)

111
4
(iii)

387
14
(iv)

441
16
(v)

389
14

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 9.

49

29

48

16

27

5

22

49

47

32

30

(i)

453
11
(ii)

455
11
(iii)

535
13
(iv)

41
(v)

371
9

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.

31

35

22

28

3

34

15

10

36

3

13

22

10

20

(i)

81
5
(ii)

145
9
(iii)

113
7
(iv)

111
7
(v)

115
7

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.

21

32

3

16

47

11

39

17

26

17

21

(i)

500
11
(ii)

590
13
(iii)

410
9
(iv)

498
11
(v)

502
11

Question 18

18.

Heights of 10 students (in cm) are given below. Find the mean height.

160

137

156

133

141

153

150

146

171

150

(i)

1497
10

cm
(ii)

1499
10

cm
(iii)

749
5

cm
(iv)

1507
10

cm
(v)

1517
10

cm

Question 19

19.

Heights of 13 plants (in cm) are given below. Find the mean height.

65

100

64

89

57

57

54

79

73

86

60

98

77

(i)

960
13

cm
(ii)

959
13

cm
(iii)

972
13

cm
(iv)

985
13

cm
(v)

961
13

cm

Question 20

20.

Ages of 14 students (in years) are given below. Find the mean age.

13

12

11

15

15

12

13

15

14

14

12

10

13

13

(i)

11

years
(ii)

12

years
(iii)

13

years
(iv)

14

years
(v)

15

years

Question 21

21.

Rainfall of 14 days (in mm) are given below. Find the mean rainfall.

13

6

7

14

8

12

13

7

15

10

12

15

6

11

(i)

177
14

mm
(ii)

163
14

mm
(iii)

151
14

mm
(iv)

75
7

mm
(v)

149
14

mm

Question 22

22.

Scores of 15 students are given below. Find the mean score.

80

72

77

84

83

87

85

71

79

77

86

70

76

82

74

(i)

1183
15
(ii)

1184
15
(iii)

1213
15
(iv)

1198
15
(v)

79

Question 23

23.

Temperatures of 15 days (in °C) are given below. Find the mean temperature.

35

35

26

26

30

30

35

32

26

28

27

31

31

34

31

(i)

457
15

°C
(ii)

472
15

°C
(iii)

458
15

°C
(iv)

153
5

°C
(v)

487
15

°C

Question 24

24.

Weights of 15 students (in kg) are given below. Find the mean weight.

56

51

54

59

44

46

55

54

57

53

41

41

57

43

44

(i)

157
3

kg
(ii)

152
3

kg
(iii)

151
3

kg
(iv)

51

kg
(v)

154
3

kg

Question 25

25.

Daily wages of 14 labourers (in ₹) are given below. Find the mean wage.

392

419

310

336

336

437

308

474

447

361

357

486

419

351

(i)

₹

388.14
(ii)

₹

390.07
(iii)

₹

388.07
(iv)

₹

389.07
(v)

₹

388.21

Question 26

26.

The arithmetic mean of a + 2, a, and a - 2 is

(i)

a
(ii)

a - 2
(iii)

a + 2
(iv)

3a

Question 27

27.

The arithmetic mean of
2

10

49

9

9

36

27

9
is

(i)

17.88
(ii)

16.88
(iii)

19.88
(iv)

20.88
(v)

18.88

Question 28

28.

If the mean of
5
samples is
31

1
5
,

what is the new mean if
9
is added to each number.

(i)

201
5
(ii)

121
3
(iii)

281
7
(iv)

203
5
(v)

199
5

Question 29

29.

If the mean of
5
samples is
21

2
5
,

what is the new mean if
4
is subtracted from each number.

(i)

89
5
(ii)

121
7
(iii)

87
5
(iv)

53
3
(v)

17

Question 30

30.

If the mean of
5
samples is
23

1
5
,

what is the new mean if each number is multiplied by
7
.

(i)

814
5
(ii)

812
5
(iii)

162
(iv)

488
3
(v)

1136
7

Question 31

31.

(i)

8
(ii)

9
(iii)

12
(iv)

11
(v)

10

Question 32

32.

(i)

19
(ii)

18
(iii)

15
(iv)

17
(v)

20

Question 33

33.

The mean of the below random sample is
32

9
10
.
Find the missing quantity.
32

x

46

22

47

44

24

28

25

15

(i)

46
(ii)

45
(iii)

43
(iv)

48
(v)

47

Assignment Key