Statistics Maths - Statistics

The difference between the highest and lowest values of the observations is called:

In a frequency distribution, ogives are graphical representation of:

The mean of a, b, c, d and e is 28. If the mean of a, c, and e is 24, what is the mean of b and d?

In the class intervals 10-20, 20-30, 20 is taken in:

In the given graph, the number of students who scored 60 or more marks is:

What value can be taken on Y -axis of frequency polygon?

What value can be taken on X-axis of frequency polygon?

What values can be taken on Y -axis to draw a histogram?

What values can be taken on X-axis of histogram?

For frequency polygon which values we take on X-axis ?

In a particular section of Class IX, 40 students were asked about the months of their birth and the following graph was prepared for the data so obtained:

Observe the bar graph given above and answer the following questions:

1. How many students were born in the month of November?
2. In which month were the maximum number of students born?

100 surnames were randomly picked up from a local telephone directory and a frequency distribution of the number of letters in the English alphabets in the surnames was found as follows :

Number of letters	Number of surnames
1-4	6
4-6	30
6-8	44
8-12	16
12-20	4

1. Draw a histogram to depict the given information.
2. Write the class interval in which the maximum number of surnames lie.

A random survey of the number of children of various age groups playing in a park was found as follows

Age (in years)	Number of children
1-2	5
2-3	3
3-5	6
5-7	12
7-10	9
10-15	10
15-17	4

Draw a histogram to represent the data above.

The runs scored by two teams A and B on the first 60 balls in a cricket match are given below :

Number of balls	Team A	Team B
1-6	2	5
7-12	1	6
13-18	8	2
19-24	9	10
25-30	4	5
31-36	5	6
37-42	6	3
43-48	10	4
49-54	6	8
55-60	2	10

Represent the data of both the teams on the same graph by frequency polygons.
[Hint: First make the class intervals continuous.]

The following table gives the distribution of students of two sections according to the marks obtained by them:

Section A		Section B
Marks	Frequency	Marks	Frequency
0-10	3	0-10	5
10-20	9	10-20	19
20-30	17	20-30	15
30-40	12	30-40	10
40-50	9	40-50	1

Represent the marks of the students of both the sections on the same graph by frequency polygons.

The following table gives the life times of 400 neon lamps :

Life time(in hours)	Number of lamps
300-400	14
400-500	56
500-600	60
600-700	86
700-800	74
800-900	62
900-1000	48

1. Represent the given information with the help of a histogram.
2. How many lamps have a life time of more than 700 hours?

Five friends Anchal, Amisha, Mahi, Vaishu and Sahar are living in a hostel. 
At the end of every month, they calculate the expenses on food and shopping.
The table given below shows their monthly expenses for the month of November.

Name	Anchal	Amisha	Mahi	Vishu	Sahar
Expenditure (in Rs)	3000	5000	6000	4500	7000

1. Which graphical representation method would best represent the data given?
2. What is the average expense of the friends for the month of November?
3. Anchal says, “The difference between the median expenditures for October and November amounts to 0% of the November expense, and we have been able to reduce our median expense for November.”
What was their median expense for the month of October? 
  A. 12π
  B. 15π
  C. 19π
  D. 20π

In a school camp, 40 students were divided into two groups to play a game.
The table given below shows the scores of team A and team B. 

Time(s) in minutes	Cumulative Score of Team A	Cumulative Score of Team A
0-5	14	20
5-10	35	27
10-15	30	31
15-20	35	31
20-25	44	37
25-30	52	50

7. How many score points did team A get between 10-15 minutes?
  A. 6
  B. 24
  C. 30
  D. 68
8. Which team scored more points during last 5 minutes? Justify your answer.
9. What is the mean number of score points obtained by team A in a 5-minute interval rounded to the nearest whole number?

Draws a graphical representation of the points scored by team B.
His graphical representation is given below.

10. Suman says, “Arun’s graphical representation is not appropriate.” 
Do you agree with Suman? Mention YES or NO. Give reason to justify your choice.

Read the Source/ Text given below and answer answer these questions:
A healthcare survey was done by the state health and family welfare care board of the state of Punjab. The data is collected by forming age groups; i.e; 10-15, 20-25 .... and so on. The overall data from a town is given below in the form of a bar graph. Read the data carefully and answer the questions that follow.

1. What is the percentage of the youngest age-group persons over those in the oldest age group?

1. 400.56%
2. 466.67%
3. 500%
4. 500.67%

2. What is the total population of the town?

1. 6800
2. 7000
3. 6700
4. 6600

3. How many persons are more in the age-group 10-15 than in the age group 30-35?

1. 100
2. 200
3. 250
4. 300

4. What is the age-group of exactly 1200 persons living in the town?

1. 20-25
2. 10-15
3. 15-20
4. 25-30

5. What is the total number of persons living in the town in the age-groups 10-15 and 60-65?

1. 2100
2. 2000
3. 2200
4. 2400