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 40 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

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


Answer:_______________




2)  

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

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


Answer:_______________




3)  

The following table shows the marks obtained by 39 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 10 11 12 13 14 15 16
frequency f 2 5 7 11 7 4 3


Answer:_______________




4)  

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

data x 7 8 9 10 11 12 13
frequency f 3 6 6 14 5 6 3


Answer:_______________




5)  

The following table shows the marks obtained by 42 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 4 6 6 10 7 4 5


Answer:_______________




6)  

The following table shows the marks obtained by 39 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 3 5 6 11 6 4 4


Answer:_______________




7)  

The following table shows the marks obtained by 36 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

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


Answer:_______________




8)  

The following table shows the marks obtained by 39 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 4 5 7 11 6 3 3


Answer:_______________




9)  

The following table shows the marks obtained by 47 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 4 6 7 15 5 5 5


Answer:_______________




10)  

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

data x 11 12 13 14 15 16 17
frequency f 2 6 7 10 6 5 4


Answer:_______________




 

1)  

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

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

Answer: 1.52


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 11

 fdfd2

8

9

10

11

12

13

14

2

4

7

14

7

2

4

16

36

70

154

84

26

56

 -3

-2

-1

0

1

2

3

-6

-8

-7

0

4

12

 18

16

7

0

7

8

36

 ∑f =40  ∑fx=442 ∑d=0∑fd= 2 ∑fd292

 

Arithmetric mean

xbar

=∑ fx
=
 
442

 
11.05
∑ f40

 

standard deviation Ô
=
 
  ∑fd2

=

    9240
  ∑f

 

 

=   2.30

= 1.52

 



2)  

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

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

Answer: 1.61


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 11

 fdfd2

8

9

10

11

12

13

14

2

8

9

11

6

6

3

16

72

90

121

72

78

42

 -3

-2

-1

0

1

2

3

-6

-16

-9

0

12

9

 18

32

9

0

6

24

27

 ∑f =45  ∑fx=491 ∑d=0∑fd= -4 ∑fd2116

 

Arithmetric mean

xbar

=∑ fx
=
 
491

 
10.91
∑ f45

 

standard deviation Ô
=
 
  ∑fd2

=

    11645
  ∑f

 

 

=   2.58

= 1.61

 



3)  

The following table shows the marks obtained by 39 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 10 11 12 13 14 15 16
frequency f 2 5 7 11 7 4 3

Answer: 1.56


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 13

 fdfd2

10

11

12

13

14

15

16

2

5

7

11

7

4

3

20

55

84

143

98

60

48

 -3

-2

-1

0

1

2

3

-6

-10

-7

0

8

9

 18

20

7

0

7

16

27

 ∑f =39  ∑fx=508 ∑d=0∑fd= 1 ∑fd295

 

Arithmetric mean

xbar

=∑ fx
=
 
508

 
13.03
∑ f39

 

standard deviation Ô
=
 
  ∑fd2

=

    9539
  ∑f

 

 

=   2.44

= 1.56

 



4)  

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

data x 7 8 9 10 11 12 13
frequency f 3 6 6 14 5 6 3

Answer: 1.62


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 10

 fdfd2

7

8

9

10

11

12

13

3

6

6

14

5

6

3

21

48

54

140

55

72

39

 -3

-2

-1

0

1

2

3

-9

-12

-6

0

12

9

 27

24

6

0

5

24

27

 ∑f =43  ∑fx=429 ∑d=0∑fd= -1 ∑fd2113

 

Arithmetric mean

xbar

=∑ fx
=
 
429

 
9.98
∑ f43

 

standard deviation Ô
=
 
  ∑fd2

=

    11343
  ∑f

 

 

=   2.63

= 1.62

 



5)  

The following table shows the marks obtained by 42 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 4 6 6 10 7 4 5

Answer: 1.79


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 10

 fdfd2

7

8

9

10

11

12

13

4

6

6

10

7

4

5

28

48

54

100

77

48

65

 -3

-2

-1

0

1

2

3

-12

-12

-6

0

8

15

 36

24

6

0

7

16

45

 ∑f =42  ∑fx=420 ∑d=0∑fd= 0 ∑fd2134

 

Arithmetric mean

xbar

=∑ fx
=
 
420

 
10.00
∑ f42

 

standard deviation Ô
=
 
  ∑fd2

=

    13442
  ∑f

 

 

=   3.19

= 1.79

 



6)  

The following table shows the marks obtained by 39 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 3 5 6 11 6 4 4

Answer: 1.69


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 10

 fdfd2

7

8

9

10

11

12

13

3

5

6

11

6

4

4

21

40

54

110

66

48

52

 -3

-2

-1

0

1

2

3

-9

-10

-6

0

8

12

 27

20

6

0

6

16

36

 ∑f =39  ∑fx=391 ∑d=0∑fd= 1 ∑fd2111

 

Arithmetric mean

xbar

=∑ fx
=
 
391

 
10.03
∑ f39

 

standard deviation Ô
=
 
  ∑fd2

=

    11139
  ∑f

 

 

=   2.85

= 1.69

 



7)  

The following table shows the marks obtained by 36 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

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

Answer: 1.67


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 13

 fdfd2

10

11

12

13

14

15

16

3

6

5

11

5

3

3

30

66

60

143

70

45

48

 -3

-2

-1

0

1

2

3

-9

-12

-5

0

6

9

 27

24

5

0

5

12

27

 ∑f =36  ∑fx=462 ∑d=0∑fd= -6 ∑fd2100

 

Arithmetric mean

xbar

=∑ fx
=
 
462

 
12.83
∑ f36

 

standard deviation Ô
=
 
  ∑fd2

=

    10036
  ∑f

 

 

=   2.78

= 1.67

 



8)  

The following table shows the marks obtained by 39 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 4 5 7 11 6 3 3

Answer: 1.66


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 10

 fdfd2

7

8

9

10

11

12

13

4

5

7

11

6

3

3

28

40

63

110

66

36

39

 -3

-2

-1

0

1

2

3

-12

-10

-7

0

6

9

 36

20

7

0

6

12

27

 ∑f =39  ∑fx=382 ∑d=0∑fd= -8 ∑fd2108

 

Arithmetric mean

xbar

=∑ fx
=
 
382

 
9.79
∑ f39

 

standard deviation Ô
=
 
  ∑fd2

=

    10839
  ∑f

 

 

=   2.77

= 1.66

 



9)  

The following table shows the marks obtained by 47 students in a Quiz competition in Mathematics. Calculate the stadard deviation.

data x 7 8 9 10 11 12 13
frequency f 4 6 7 15 5 5 5

Answer: 1.71


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 10

 fdfd2

7

8

9

10

11

12

13

4

6

7

15

5

5

5

28

48

63

150

55

60

65

 -3

-2

-1

0

1

2

3

-12

-12

-7

0

10

15

 36

24

7

0

5

20

45

 ∑f =47  ∑fx=469 ∑d=0∑fd= -1 ∑fd2137

 

Arithmetric mean

xbar

=∑ fx
=
 
469

 
9.98
∑ f47

 

standard deviation Ô
=
 
  ∑fd2

=

    13747
  ∑f

 

 

=   2.91

= 1.71

 



10)  

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

data x 11 12 13 14 15 16 17
frequency f 2 6 7 10 6 5 4

Answer: 1.67


SOLUTION 1 :

 

xffx

d = x-xbar

= x - 14

 fdfd2

11

12

13

14

15

16

17

2

6

7

10

6

5

4

22

72

91

140

90

80

68

 -3

-2

-1

0

1

2

3

-6

-12

-7

0

10

12

 18

24

7

0

6

20

36

 ∑f =40  ∑fx=563 ∑d=0∑fd= 3 ∑fd2111

 

Arithmetric mean

xbar

=∑ fx
=
 
563

 
14.08
∑ f40

 

standard deviation Ô
=
 
  ∑fd2

=

    11140
  ∑f

 

 

=   2.78

= 1.67