Data Handling - Class 7 - Mathematics
Renews every month. Cancel anytime
Your personal doubt-solving assistant
Chatterbot AI gives you 100% accurate answers to your questions in an instant.
Examples - Data Handling | NCERT | Mathematics | Class 7
Ashish studies for 4 hours, 5 hours and 3 hours, respectively, on three consecutive days. How many hours does he study daily on an average?
To find the average number of hours Ashish studies daily, we add the hours he studies each day and then divide by the number of days.
The total hours Ashish studies are 4 hours + 5 hours + 3 hours = 12 hours.
Since these hours are for 3 consecutive days, we divide the total hours by 3.
So, the average daily study hours are:
$$ \frac{12 \text{ hours}}{3 \text{ days}} = 4 \text{ hours per day}. $$
A batsman scored the following number of runs in six innings:
$$ 36,35,50,46,60,55 $$
Calculate the mean runs scored by him in an inning.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowThe ages in years of 10 teachers of a school are:
$$ 32,41,28,54,35,26,23,33,38,40 $$
(i) What is the age of the oldest teacher and that of the youngest teacher? with steps
(ii) What is the range of the ages of the teachers?with steps
(iii) What is the mean age of these teachers?with steps
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowFind the mode of the given set of numbers: 1, 1, 2, 4, 3, 2, 1, 2, 2, 4 with steps
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowFollowing are the margins of victory in the football matches of a league.
$$ \begin{aligned} & 1,3,2,5,1,4,6,2,5,2,2,2,4,1,2,3,1,1,2,3,2 \\ & 6,4,3,2,1,1,4,2,1,5,3,3,2,3,2,4,2,1,2 \end{aligned} $$
Find the mode of this data. with steps
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowFind the mode of the numbers: 2, 2, 2, 3, 3, 4, 5, 5, 5, 6, 6, 8 with steps
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowFind the median of the data: 24, 36, 46, 17, 18, 25, 35 with steps
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowTwo hundred students of $6^{\text {th }}$ and $7^{\text {th }}$ classes were asked to name their favourite colour so as to decide upon what should be the colour of their school building. The results are shown in the following table. Represent the given data on a bar graph.
Favourite Colour | Red | Green | Blue | Yellow | Orange |
---|---|---|---|---|---|
Number of Students | 43 | 19 | 55 | 49 | 34 |
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowFollowing data gives total marks (out of 600) obtained by six children of a particular class. Represent the data on a bar graph.
Students | Ajay | Bali | Dipti | Faiyaz | Geetika | Hari |
---|---|---|---|---|---|---|
Marks Obtained | 450 | 500 | 300 | 360 | 400 | 540 |
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowA mathematics teacher wants to see, whether the new technique of teaching she applied after quarterly test was effective or not. She takes the scores of the 5 weakest children in the quarterly test (out of 25 ) and in the half yearly test (out of 25 ):
Students | Ashish | Arun | Kavish | Maya | Rita |
---|---|---|---|---|---|
Quarterly | 10 | 15 | 12 | 20 | 9 |
Half yearly | 15 | 18 | 16 | 21 | 15 |
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowExercise 3.1 - Data Handling | NCERT | Mathematics | Class 7
Find the range of heights of the ten students of your class.
Let us assume the heights (in cm) of 10 students of our class as :
120, 122, 125, 137, 139, 150, 142, 133, 145, 158
To find the range of heights for the students, you need to subtract the minimum height from the maximum height in the set of heights provided. The heights (in cm) of 10 students are as follows:
120, 122, 125, 137, 139, 150, 142, 133, 145, 158.
First, identify the minimum and maximum heights in this data:
Minimum height = 120 cm
Maximum height = 158 cm
Next, calculate the range by subtracting the minimum height from the maximum height:
$$\text{Range} = \text{Maximum height} - \text{Minimum height}$$ $$\text{Range} = 158 - 120$$ $$\text{Range} = 38 \text{ cm}$$
Therefore, the range of heights of the ten students is 38 cm.
Organise the following marks in a class assessment, in a tabular form.
$$4,6,7,5,3,5,4,5,2,6,2,5,1,9,6,5,8,4,6,7$$
(i) Which number is the highest?
(ii) Which number is the lowest?
(iii) What is the range of the data?
(iv) Find the arithmetic mean.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowFind the mean of the first five whole numbers.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowA cricketer scores the following runs in eight innings:
$$58,76,40,35,46,45,0,100 .$$
Find the mean score.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowFollowing table shows the points of each player scored in four games:
Player | Game 1 | Game 2 | Game 3 | Game 4 |
---|---|---|---|---|
A | 14 | 16 | 10 | 10 |
B | 0 | 8 | 6 | 4 |
C | 8 | 11 | did not play | 13 |
Now answer the following questions:
(i) Find the mean to determine A's average number of points scored per game.
(ii) To find the mean number of points per game for $\mathrm{C}$, would you divide the total points by 3 or by 4 ? Why?
(iii) B played in all the four games. How would you find the mean?
(iv) Who is the best performer?
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowThe marks (out of 100) obtained by a group of students in a science test are 85, 76, $90,85,39,48,56,95,81$ and 75. Find the:
(i) Highest and the lowest marks obtained by the students.
(ii) Range of the marks obtained.
(iii) Mean marks obtained by the group.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowThe enrolment in a school during six consecutive years was as follows:
$1555,1670,1750,2013,2540,2820$
Find the mean enrolment of the school for this period.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowThe rainfall (in $\mathrm{mm}$ ) in a city on 7 days of a certain week was recorded as follows:
Day | Mon | Tue | Wed | Thurs | Fri | Sat | Sun |
---|---|---|---|---|---|---|---|
Rainfall (in mm) | 0.0 | 12.2 | 2.1 | 0.0 | 20.5 | 5.5 | 1.0 |
(i) Find the range of the rainfall in the above data.
(ii) Find the mean rainfall for the week.
(iii) On how many days was the rainfall less than the mean rainfall.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowThe heights of 10 girls were measured in $\mathrm{cm}$ and the results are as follows: 135, 150, 139, 128, 151, 132, 146, 149, 143, 141.
(i) What is the height of the tallest girl?
(ii) What is the height of the shortest girl?
(iii) What is the range of the data?
(iv) What is the mean height of the girls?
(v) How many girls have heights more than the mean height.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowExercise 3.2 - Data Handling | NCERT | Mathematics | Class 7
The scores in mathematics test (out of 25 ) of 15 students is as follows:
$$
19,25,23,20,9,20,15,10,5,16,25,20,24,12,20
$$
Find the mode and median of this data. Are they same?
The mode of the data is $20$, and the median is also $20$. Thus, for this set of data, the mode and median are the same.
The runs scored in a cricket match by 11 players is as follows:
$$
6,15,120,50,100,80,10,15,8,10,15
$$
Find the mean, mode and median of this data. Are the three same?
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowThe weights (in kg.) of 15 students of a class are:
$$
38,42,35,37,45,50,32,43,43,40,36,38,43,38,47
$$
(i) Find the mode and median of this data.
(ii) Is there more than one mode?
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowFind the mode and median of the data: $13,16,12,14,19,12,14,13,14$
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowTell whether the statement is true or false:
(i) The mode is always one of the numbers in a data.
(ii) The mean is one of the numbers in a data.
(iii) The median is always one of the numbers in a data.
(iv) The data $6,4,3,8,9,12,13,9$ has mean 9.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowExercise 3.3 - Data Handling | NCERT | Mathematics | Class 7
Use the bar graph (Fig 3.3) to answer the following questions.
(a) Which is the most popular pet?
(b) How many students have dog as a pet?
Based on the data given, we can answer the following questions:
(a) The most popular pet is the one with the highest count. According to the data provided:
Dogs: 8
Cats: 10
Rabbits: 2
Hamsters: 5
Others: 3
Thus, Cats are the most popular pet with 10 votes.
(b) The number of students who have a dog as a pet is 8.
Read the bar graph (Fig 3.4) 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 years were fewer than 250 books sold?
(iv) Can you explain how you would estimate the number of books sold in 1989 ?
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowNumber 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 | 90 |
(a) How would you choose a scale?
(b) Answer the following questions:
(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 eight.
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowThe performance of a student in $1^{\text {st }}$ Term and $2^{\text {nd }}$ Term is given. Draw a double bar graph choosing appropriate scale and answer the following:
Subject | English | Hindi | Maths | Science | S. Science |
---|---|---|---|---|---|
$\mathbf{1}^{\text {st }}$ | 67 | 72 | 88 | 81 | 73 |
$2^{\text {nd }}$ | 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?
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowConsider this data collected from a survey of a colony.
Favourite Sport | Cricket | Basket Ball | Swimming | Hockey | Athletics |
---|---|---|---|---|---|
Watching | 1240 | 470 | 510 | 430 | 250 |
Participating | 620 | 320 | 320 | 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?
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowTake the data giving the minimum and the maximum temperature of various cities given in the beginning of this Chapter (Table 3.1). 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 | $38^ \circ \mathrm{C}$ | $29^ \circ \mathrm{C}$ |
Amritsar | $37^ \circ \mathrm{C}$ | $26^ \circ \mathrm{C}$ |
Bangalore | $28^ \circ \mathrm{C}$ | $21^ \circ \mathrm{C}$ |
Chennai | $36^ \circ \mathrm{C}$ | $27^ \circ \mathrm{C}$ |
Delhi | $38^ \circ \mathrm{C}$ | $28^ \circ \mathrm{C}$ |
Jaipur | $39^ \circ \mathrm{C}$ | $29^ \circ \mathrm{C}$ |
Jammu | $41^ \circ \mathrm{C}$ | $26^ \circ \mathrm{C}$ |
Mumbai | $32^ \circ \mathrm{C}$ | $27^ \circ \mathrm{C}$ |
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowExtra Questions - Data Handling | NCERT | Mathematics | Class 7
A large number of enumerators are required to collect primary data on a large scale, in contrast to secondary data.
A) True
B) False
Correct answer: A) True
Explanation:
Primary data refers to data collected firsthand for a specific purpose. Therefore, collecting primary data on a large scale typically necessitates a large number of enumerators. This is because each data point must be personally gathered, observed, or recorded.
On the other hand, secondary data is data that was already collected by others and is being reused. Since this data has already been compiled and organized, no enumerators are needed to gather it anew.
The value of the range for the data set ${-10, -5, -1, -4, -6, -7}$ is .
(A) -9
(B) 9
(C) 11
(D) -11
Improve your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowImprove your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowImprove your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowImprove your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowImprove your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowImprove your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowImprove your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up nowImprove your grades!
Join English Chatterbox to access detailed and curated answers, and score higher than you ever have in your exams.
Sign up now