Scroll:statistics >> standard deviation >> saq (4242)


Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.



 

1)  

The following table shows the marks obtained by 41 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 8 9 10 11 12 13 14
frequency f 3 6 6 13 6 3 4


Answer:_______________




2)  

The following table shows the marks obtained by 40 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 9 10 11 12 13 14 15
frequency f 3 5 7 10 6 5 4


Answer:_______________




3)  

The following table shows the marks obtained by 40 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 3 6 5 12 6 3 5


Answer:_______________




4)  

The following table shows the marks obtained by 44 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 10 11 12 13 14 15 16
frequency f 4 8 8 11 5 3 5


Answer:_______________




5)  

The following table shows the marks obtained by 37 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 8 9 10 11 12 13 14
frequency f 3 6 5 10 5 4 4


Answer:_______________




6)  

The following table shows the marks obtained by 43 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 8 9 10 11 12 13 14
frequency f 2 6 9 12 7 3 4


Answer:_______________




7)  

The following table shows the marks obtained by 37 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 10 11 12 13 14 15 16
frequency f 2 4 6 12 7 3 3


Answer:_______________




8)  

The following table shows the marks obtained by 44 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 9 10 11 12 13 14 15
frequency f 4 4 6 15 6 5 4


Answer:_______________




9)  

The following table shows the marks obtained by 45 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 10 11 12 13 14 15 16
frequency f 3 7 6 14 7 5 3


Answer:_______________




10)  

The following table shows the marks obtained by 41 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 2 4 9 12 7 2 5


Answer:_______________




 

1)  

The following table shows the marks obtained by 41 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 8 9 10 11 12 13 14
frequency f 3 6 6 13 6 3 4

Answer: 1.65


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 11

 fdfd2

8

9

10

11

12

13

14

3

6

6

13

6

3

4

24

54

60

143

72

39

56

 -3

-2

-1

0

1

2

3

-9

-12

-6

0

6

12

 27

24

6

0

6

12

36

 ∑f =41  ∑fx=448 ∑d=0∑fd= -3 ∑fd2111

 

Arithmetric mean

xbar

=∑ fx
=
 
448

 
10.93
∑ f41

 

standard deviation Ô
=
 
  ∑fd2

=

    11141
  ∑f

 

 

=   2.71

= 1.65

 



2)  

The following table shows the marks obtained by 40 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 9 10 11 12 13 14 15
frequency f 3 5 7 10 6 5 4

Answer: 1.70


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 12

 fdfd2

9

10

11

12

13

14

15

3

5

7

10

6

5

4

27

50

77

120

78

70

60

 -3

-2

-1

0

1

2

3

-9

-10

-7

0

10

12

 27

20

7

0

6

20

36

 ∑f =40  ∑fx=482 ∑d=0∑fd= 2 ∑fd2116

 

Arithmetric mean

xbar

=∑ fx
=
 
482

 
12.05
∑ f40

 

standard deviation Ô
=
 
  ∑fd2

=

    11640
  ∑f

 

 

=   2.90

= 1.70

 



3)  

The following table shows the marks obtained by 40 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 3 6 5 12 6 3 5

Answer: 1.73


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 10

 fdfd2

7

8

9

10

11

12

13

3

6

5

12

6

3

5

21

48

45

120

66

36

65

 -3

-2

-1

0

1

2

3

-9

-12

-5

0

6

15

 27

24

5

0

6

12

45

 ∑f =40  ∑fx=401 ∑d=0∑fd= 1 ∑fd2119

 

Arithmetric mean

xbar

=∑ fx
=
 
401

 
10.03
∑ f40

 

standard deviation Ô
=
 
  ∑fd2

=

    11940
  ∑f

 

 

=   2.98

= 1.73

 



4)  

The following table shows the marks obtained by 44 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 10 11 12 13 14 15 16
frequency f 4 8 8 11 5 3 5

Answer: 1.77


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 13

 fdfd2

10

11

12

13

14

15

16

4

8

8

11

5

3

5

40

88

96

143

70

45

80

 -3

-2

-1

0

1

2

3

-12

-16

-8

0

6

15

 36

32

8

0

5

12

45

 ∑f =44  ∑fx=562 ∑d=0∑fd= -10 ∑fd2138

 

Arithmetric mean

xbar

=∑ fx
=
 
562

 
12.77
∑ f44

 

standard deviation Ô
=
 
  ∑fd2

=

    13844
  ∑f

 

 

=   3.14

= 1.77

 



5)  

The following table shows the marks obtained by 37 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 8 9 10 11 12 13 14
frequency f 3 6 5 10 5 4 4

Answer: 1.75


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 11

 fdfd2

8

9

10

11

12

13

14

3

6

5

10

5

4

4

24

54

50

110

60

52

56

 -3

-2

-1

0

1

2

3

-9

-12

-5

0

8

12

 27

24

5

0

5

16

36

 ∑f =37  ∑fx=406 ∑d=0∑fd= -1 ∑fd2113

 

Arithmetric mean

xbar

=∑ fx
=
 
406

 
10.97
∑ f37

 

standard deviation Ô
=
 
  ∑fd2

=

    11337
  ∑f

 

 

=   3.05

= 1.75

 



6)  

The following table shows the marks obtained by 43 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 8 9 10 11 12 13 14
frequency f 2 6 9 12 7 3 4

Answer: 1.57


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 11

 fdfd2

8

9

10

11

12

13

14

2

6

9

12

7

3

4

16

54

90

132

84

39

56

 -3

-2

-1

0

1

2

3

-6

-12

-9

0

6

12

 18

24

9

0

7

12

36

 ∑f =43  ∑fx=471 ∑d=0∑fd= -2 ∑fd2106

 

Arithmetric mean

xbar

=∑ fx
=
 
471

 
10.95
∑ f43

 

standard deviation Ô
=
 
  ∑fd2

=

    10643
  ∑f

 

 

=   2.47

= 1.57

 



7)  

The following table shows the marks obtained by 37 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 10 11 12 13 14 15 16
frequency f 2 4 6 12 7 3 3

Answer: 1.52


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 13

 fdfd2

10

11

12

13

14

15

16

2

4

6

12

7

3

3

20

44

72

156

98

45

48

 -3

-2

-1

0

1

2

3

-6

-8

-6

0

6

9

 18

16

6

0

7

12

27

 ∑f =37  ∑fx=483 ∑d=0∑fd= 2 ∑fd286

 

Arithmetric mean

xbar

=∑ fx
=
 
483

 
13.05
∑ f37

 

standard deviation Ô
=
 
  ∑fd2

=

    8637
  ∑f

 

 

=   2.32

= 1.52

 



8)  

The following table shows the marks obtained by 44 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 9 10 11 12 13 14 15
frequency f 4 4 6 15 6 5 4

Answer: 1.65


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 12

 fdfd2

9

10

11

12

13

14

15

4

4

6

15

6

5

4

36

40

66

180

78

70

60

 -3

-2

-1

0

1

2

3

-12

-8

-6

0

10

12

 36

16

6

0

6

20

36

 ∑f =44  ∑fx=530 ∑d=0∑fd= 2 ∑fd2120

 

Arithmetric mean

xbar

=∑ fx
=
 
530

 
12.05
∑ f44

 

standard deviation Ô
=
 
  ∑fd2

=

    12044
  ∑f

 

 

=   2.73

= 1.65

 



9)  

The following table shows the marks obtained by 45 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 10 11 12 13 14 15 16
frequency f 3 7 6 14 7 5 3

Answer: 1.60


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 13

 fdfd2

10

11

12

13

14

15

16

3

7

6

14

7

5

3

30

77

72

182

98

75

48

 -3

-2

-1

0

1

2

3

-9

-14

-6

0

10

9

 27

28

6

0

7

20

27

 ∑f =45  ∑fx=582 ∑d=0∑fd= -3 ∑fd2115

 

Arithmetric mean

xbar

=∑ fx
=
 
582

 
12.93
∑ f45

 

standard deviation Ô
=
 
  ∑fd2

=

    11545
  ∑f

 

 

=   2.56

= 1.60

 



10)  

The following table shows the marks obtained by 41 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 2 4 9 12 7 2 5

Answer: 1.58


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 10

 fdfd2

7

8

9

10

11

12

13

2

4

9

12

7

2

5

14

32

81

120

77

24

65

 -3

-2

-1

0

1

2

3

-6

-8

-9

0

4

15

 18

16

9

0

7

8

45

 ∑f =41  ∑fx=413 ∑d=0∑fd= 3 ∑fd2103

 

Arithmetric mean

xbar

=∑ fx
=
 
413

 
10.07
∑ f41

 

standard deviation Ô
=
 
  ∑fd2

=

    10341
  ∑f

 

 

=   2.51

= 1.58