NCERT Solutions for Class 7 Maths Chapter 3 Data Handling Ex 3.3

# NCERT Solutions for Class 7 Maths Chapter 3 Data Handling Ex 3.3

NCERT Solutions for Class 7 Maths Chapter 3 Data Handling Ex 3.3 are the part of NCERT Solutions for Class 7 Maths (Rationalised Contents). Here you can find the NCERT Solutions for Class 7 Maths Chapter 3 Data Handling Ex 3.3.

## NCERT Solutions for Class 7 Maths Chapter 3 Data Handling Ex 3.3 (Rationalised Contents)

### Ex 3.3 Class 7 Maths Question 1.

Use the bar graph to answer the following questions.

(a) Which is the most popular pet?
(b) How many students have dog as a pet?

Solution:
From the given bar graph, we have
(a) The cats are the most popular pet among the students. Because 10 students own it.
(b) 8 students have dog as a pet.

### Ex 3.3 Class 7 Maths Question 2.

Read the bar graph which shows the number of books sold by a bookstore during five consecutive years and answer the following questions:

(i) About how many books were sold in 1989, 1990, 1992?
(ii) In which year were about 475 books sold? About 225 books sold?
(iii) In which year were fewer than 250 books sold?
(iv) Can you explain how you would estimate the number of books sold in 1989?

Solution:
From the given bar graph, we have
(i) The number of books sold in the year 1989 is about 180, in the year 1990 is about 475 and in the year 1992 is about 225.
(ii) About 475 books were sold in 1990. About 225 books were sold in 1992.
(iii) Fewer than 250 books were sold in the years 1989 and 1992.
(iv) On y-axis, the line is divided into 10 small parts of 10 books each. So, we can estimate the number of books sold in the year 1989 is about 180.

### Ex 3.3 Class 7 Maths Question 3.

Number of children in six different classes are given below. Represent the data on a bar graph.

 Class Fifth Sixth Seventh Eighth Ninth Tenth Number of children 135 120 95 100 90 80

(a) How would you choose a scale?

(i) Which class has the maximum number of children? And the minimum?

(ii) Find the ratio of students of class sixth to the students of class eighth.

Solution:

(a) Scale on y-axis: 1 cm = 10 students
(b) (i) Class fifth has the maximum number of children, i.e., 135.
Class tenth has the minimum number of children, i.e., 80.

(ii) Number of students in class sixth = 120

Number of students in class eighth = 100
Ratio of the students of class sixth to the students of class eighth

= 120/100 = 6/5

= 6 : 5

### Ex 3.3 Class 7 Maths Question 4.

The performance of a student in 1st term and 2nd term is given. Draw a double bar graph choosing appropriate scale and answer the following:

 Subject English Hindi Maths Science S. Science 1st term (M.M. 100) 67 72 88 81 73 2nd term (M.M. 100) 70 65 95 85 75

(i) In which subject, has the child improved his performance the most?
(ii) In which subject is the improvement the least?

(iii) Has the performance gone down in any subject?

Solution:

(i) In maths, the performance of the student improved the most.
(ii) In s. science, the performance of the student improved the least.
(iii) Yes, in Hindi the performance of the student has gone down.

### Ex 3.3 Class 7 Maths Question 5.

Consider this data collected from a survey of a colony.

 Favourite sport Watching Participating Cricket 1240 620 Basket ball 470 320 Swimming 510 320 Hockey 430 250 Athletics 250 105

(i) Draw a double bar graph choosing an appropriate scale. What do you infer from the bar graph?
(ii) Which sport is most popular?
(iii) Which is more preferred, watching or participating in sports?

Solution:
(i) The bar graph depicts the number of people who are watching and who are participating in sports.

(ii) The most popular sport is cricket.
(iii) Watching the sports is more preferred by the people.

### Ex 3.3 Class 7 Maths Question 6.

Take the data giving the minimum and the maximum temperature of various cities given in the beginning of this chapter. Plot a double bar graph using the data and answer the following:
(i) Which city has the largest difference in the minimum and maximum temperature on the given date?
(ii) Which is the hottest city and which is the coldest city?
(iii) Name two cities where maximum temperature of one was less than the minimum temperature of the other.
(iv) Name the city which has the least difference between its minimum and the maximum temperature.

Temperature of cities as on 20.6.2006

 City Max. Min. Ahmedabad 38°C 29°C Amritsar 37°C 26°C Bengaluru 28°C 21°C Chennai 36°C 27°C Delhi 38°C 28°C Jaipur 39°C 29°C Jammu 41°C 26°C Mumbai 32°C 27°C

Solution:
Double bar graph is as follows:

(i) Jammu has the largest difference between the maximum and minimum temperature, i.e., 41°C – 26°C = 15°C
(ii) Hottest city is Jammu with 41°C temperature and coldest city is Bengaluru with 21°C temperature.
(iii) (a) Bengaluru having its maximum temperature 28°C is less than the minimum temperature 29°C in Ahmedabad.

(b) Bengaluru having its maximum temperature 28°C is less than the minimum temperature 29°C in Jaipur.

(iv) Mumbai has the least difference between its minimum and maximum temperatures, i.e., 32°C – 27°C = 5°C