**Exercise 23.1**

**Question 1: The following table shows the daily production of T.V. sets in an industry for 7 days of a week.**

**Represent the above information by a pictograph.**

**Solution:**

**Question 2: The following table shows the number of Maruti cars sold by five dealers in a particular month:**

**Represent the above information by a pictograph.**

**Solution:**

**Question 3: The population of Delhi State in different census years is as given below:**

**Represent the above information with the help of a bar graph.**

**Solution:**

**Question 4: Read the bar graph shown below and answer the following questions:**

**(i) What is the information given by the bar graph?**

**(ii) How many tickets of Assam State Lottery were sold by the agent?**

**(iii) Of which state, were the maximum number of tickets sold?**

**(iv) State whether true or false.**

**The maximum number of tickets sold is three times the minimum number of tickets sold.**

**(v) Of which state were the minimum numbers of tickets sold?**

**Solution:**

**Question 5: Study the bar graph representing the number of persons in various age groups in a town shown in figure. Observe the bar graph and answer the following questions:**

**(i) What is the percentage of the youngest age-group persons over those in the oldest age group?**

**(ii) What is the total population of the town?**

**(iii) What is the number of persons in the age-group 60-65?**

**(iv) How many persons are more in the age-group 10-15 than in the age group 30-35?**

**(v) What is the age-group of exactly 1200 persons living in the town?**

**(vi) What is the total number of persons living in the town in the age-group 50-55?**

**(vii) What is the total number of persons living in the town in the age-groups 10-15 and 60-65?**

**(vii) Whether the population in general increases, decreases or remains constant with the increase in the age-group.**

**Solution:**

**Exercise 23.2**

**Question 1: Explain the reading and interpretation of bar graphs.**

**Solution:**

**Question 2: Read the following bar graph and answer the following questions:**

**(i) What information is given by the bar graph?**

**(ii) In which year the export is minimum?**

**(iii) In which year the import is maximum?**

**(iv) In which year the difference of the values of export and import is maximum?**

**Solution:**

**Question 3: The following bar graph shows the results of an annual examination in a secondary school. Read the bar graph given below, and choose the correct alternative in each of the following:**

**(i)The pair of classes in which the results of boys and girls are inversely proportional are:**

**(a) VI, VIII (b) VI, IX (c) VII, IX (d) VIII, X**

**(ii) The class having the lowest failure rate of girls is:**

**(a) VI (b) X (c) IX (d) VIII**

**(iii) The class having the lowest pass rate of students is:**

**(a) VI (b) VII (c) VIII (d) IX**

**Solution:**

**Question 4: The following data gives the number (in thousands) of applicants registered with an Employment Exchange during 1995-2000:**

**Construct a bar graph to represent the above data.**

**Solution:**

**Question 5: The production of saleable steel in some of the steel plants of our country during 1999 is given below:**

**Construct a bar graph to represent the above data on a graph paper by using the scale 1 big divisions = 20 thousand tonnes.**

**Solution:**

**Question 6: The following table gives the route length (in thousand kilometres) of the Indian Railways in some of the years:**

**Represent the above data with the help of a bar graph.**

**Solution:**

**Exercise 23.3**

**Question 1: Construct a histogram for the following data:**

**Solution:**

**Question 2: The distribution of heights (in cm) of 96 children is given below. Construct a histogram and a frequency polygon on the same axes.**

**Solution:**

**Question 3: The time taken, in seconds, to solve a problem by each of 25 pupils is as follows:**

**16, 20, 26, 27, 28, 30, 33, 37, 38, 40, 42, 43, 46, 46, 46, 48, 49, 50, 53, 58, 59, 60, 64, 52, 20**

**(a) Construct a frequency distribution for these data, using a class interval of 10 seconds.**

**(b) Draw a histogram to represent the frequency distribution.**

**Solution:**

**Question 4: Draw, in the same diagram, a histogram and a frequency polygon to represent the following data which shows the monthly cost of living index of a city in a period of 2 years:**

**Solution:**