Exercise 12.1

1. A survey conducted by an organisation for the cause of illness and death among the women between the ages 15 - 44 (in years) worldwide, found the following figures (in %).

(i) Represent the information given above graphically.

(ii) Which condition is the major cause of women’s ill health and death worldwide?

Reproductive health conditionsCardiovascular conditionsNeuropsychiatric conditions can be considered as major cause of women’s ill health and death worldwide.

(iii) Try to find out, with the help of your teacher, any two factors which play a major role in the cause in (ii) above being the major cause.

2. The following data on the number of girls (to the nearest ten) per thousand boys in different sections of Indian society is given below.

(i) Represent the information above by a bar graph.

(ii) In the classroom discuss what conclusions can be arrived at from the graph.

From the above graph, we can conclude that the maxminumminimum number of girls per thousand boys is present in section ST. We can aslo observe that the backward districts and rural areas have moreless girls per thosand boys than non-backward districts and urban areas.

3. Given below are the seats won by different political parties in the polling outcome of a state assembly elections.

(i) Draw a bar graph to represent the polling results.

(ii) Which political party won the maximum number of seats?

Party ABCDEF won the maximum number of seats.

4. The length of 40 leaves of a plant are measured correct to one millimetre, and the obtained data is represented in the following table.

(i) Draw a histogram to represent the given data. [Hint: First make the class intervals continuous]

(ii) Is there any other suitable graphical representation for the same data?

YesNo

The data given in the quetsion can also be represented by a frequency polygon.

(iii) Is it correct to conclude that the maximum number of leaves are 153 mm long? Why?

NoYes

We cannot conclude that the maximum number of leaves is 153 mm long bacause the maximumminimum number of leaves are lying in between the length of 144.5 - 153.5

5. The following table gives the life times of 400 neon lamps.

(i) Represent the given information with the help of a histogram.

(ii) How many lamps have a life time of more than 700 hours?

700 lies in the class intervals 700 - 800 , 800 - 900 , 900 - 1000.

Hence, their corresponding frequencies when added up will be ( 74 + 62 + 48 ) = lamps.

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

Represent the marks of the students of both the sections on the same graph by two frequency polygons. From the two polygons compare the performance of the two sections.

[-]Red Indicate Section A

[-]Green Indicate Section B

It can be observed that the performance of students of section ‘A’ is betterworse than the students of section ‘B’ in terms of good marks.

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

Represent the data of both the teams on the same graph by frequency polygons.

[Hint : First make the class intervals continuous]

[-]Blue Indicate Team A

[-]Yellow Indicate Team B

Solution:

Since the given intervals (e.g., 1–6, 7–12) are not continuous, we need to adjust them by subtracting 0.5 from the lower limit and adding 0.5 to the upper limit: