Page 1
Area and its Boundary
Both could not make out whose
piecewasbigger.
Suggest some ways to find out
whosepieceisbigger.Discuss.
A friend of Parth and Gini showed
oneway,usingsmallsquares.
h
WhoseSliceisBigger?
ParthandGinibought (dried
mangoslice)fromashop.
Theirpieceslookedlikethese.
aampaapad
6 cm
5 cm
Piece A
Piece B
11 cm
3 cm
ThelengthofpieceAis6cm.
So6squaresofside1cmcanbearrangedalongitslength.
ThewidthofpieceAis5cm.
So5squarescanbearrangedalongitswidth.
11
CoverwithStamps
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
India 25
146 147
Reprint 2024-25
Page 2
Area and its Boundary
Both could not make out whose
piecewasbigger.
Suggest some ways to find out
whosepieceisbigger.Discuss.
A friend of Parth and Gini showed
oneway,usingsmallsquares.
h
WhoseSliceisBigger?
ParthandGinibought (dried
mangoslice)fromashop.
Theirpieceslookedlikethese.
aampaapad
6 cm
5 cm
Piece A
Piece B
11 cm
3 cm
ThelengthofpieceAis6cm.
So6squaresofside1cmcanbearrangedalongitslength.
ThewidthofpieceAis5cm.
So5squarescanbearrangedalongitswidth.
11
CoverwithStamps
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
India 25
146 147
Reprint 2024-25
h Altogether how many squares can be arranged on it? ________
h So the area of piece A = ________ square cm
h In the same way find the area of piece B.
h Who had the bigger piece? How much bigger?
Cover with Stamps
This stamp has an area of 4 square cm. Guess how many such
stamps will cover this big rectangle.
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
Hkkjr India 25
147
Reprint 2024-25
Page 3
Area and its Boundary
Both could not make out whose
piecewasbigger.
Suggest some ways to find out
whosepieceisbigger.Discuss.
A friend of Parth and Gini showed
oneway,usingsmallsquares.
h
WhoseSliceisBigger?
ParthandGinibought (dried
mangoslice)fromashop.
Theirpieceslookedlikethese.
aampaapad
6 cm
5 cm
Piece A
Piece B
11 cm
3 cm
ThelengthofpieceAis6cm.
So6squaresofside1cmcanbearrangedalongitslength.
ThewidthofpieceAis5cm.
So5squarescanbearrangedalongitswidth.
11
CoverwithStamps
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
India 25
146 147
Reprint 2024-25
h Altogether how many squares can be arranged on it? ________
h So the area of piece A = ________ square cm
h In the same way find the area of piece B.
h Who had the bigger piece? How much bigger?
Cover with Stamps
This stamp has an area of 4 square cm. Guess how many such
stamps will cover this big rectangle.
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
Hkkjr India 25
147
Reprint 2024-25
Checkyourguess
a) Measure the yellow rectangle. It is ________ cm long.
b) How many stamps can be placed along its length? ________
c) How wide is the rectangle? ________ cm
d) How many stamps can be placed along its width? ________
e) How many stamps are needed to cover the rectangle? ________
f) How close was your earlier guess? Discuss.
g) What is the area of the rectangle? ________ square cm
h) What is the perimeter of the rectangle? ________ cm
Practicetime
a) Arbaz plans to tile his kitchen floor with
green square tiles. Each side of the tile is 10
cm. His kitchen is 220 cm in length and 180
cm wide. How many tiles will he need?
b) The fencing of a square garden is 20 m in length. How long is
one side of the garden?
c) A thin wire 20 centimetres long is formed into a
rectangle. If the width of this rectangle is
4 centimetres, what is its length?
This Guess and check activity can be done in the class by making use of other things
present. For example: how many postcards can be placed on the top of the mathematics
book, how many charts will cover the classroom walls, etc? Children can be asked to check
their guesses by tiling things wherever possible. Once they are able to make close guesses,
this work can be further extended by asking them to guess the area in terms of square cm.
‘ ’
MyBeltisLongest!
This triangle
is half of the
cm square
148 149
Reprint 2024-25
Page 4
Area and its Boundary
Both could not make out whose
piecewasbigger.
Suggest some ways to find out
whosepieceisbigger.Discuss.
A friend of Parth and Gini showed
oneway,usingsmallsquares.
h
WhoseSliceisBigger?
ParthandGinibought (dried
mangoslice)fromashop.
Theirpieceslookedlikethese.
aampaapad
6 cm
5 cm
Piece A
Piece B
11 cm
3 cm
ThelengthofpieceAis6cm.
So6squaresofside1cmcanbearrangedalongitslength.
ThewidthofpieceAis5cm.
So5squarescanbearrangedalongitswidth.
11
CoverwithStamps
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
India 25
146 147
Reprint 2024-25
h Altogether how many squares can be arranged on it? ________
h So the area of piece A = ________ square cm
h In the same way find the area of piece B.
h Who had the bigger piece? How much bigger?
Cover with Stamps
This stamp has an area of 4 square cm. Guess how many such
stamps will cover this big rectangle.
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
Hkkjr India 25
147
Reprint 2024-25
Checkyourguess
a) Measure the yellow rectangle. It is ________ cm long.
b) How many stamps can be placed along its length? ________
c) How wide is the rectangle? ________ cm
d) How many stamps can be placed along its width? ________
e) How many stamps are needed to cover the rectangle? ________
f) How close was your earlier guess? Discuss.
g) What is the area of the rectangle? ________ square cm
h) What is the perimeter of the rectangle? ________ cm
Practicetime
a) Arbaz plans to tile his kitchen floor with
green square tiles. Each side of the tile is 10
cm. His kitchen is 220 cm in length and 180
cm wide. How many tiles will he need?
b) The fencing of a square garden is 20 m in length. How long is
one side of the garden?
c) A thin wire 20 centimetres long is formed into a
rectangle. If the width of this rectangle is
4 centimetres, what is its length?
This Guess and check activity can be done in the class by making use of other things
present. For example: how many postcards can be placed on the top of the mathematics
book, how many charts will cover the classroom walls, etc? Children can be asked to check
their guesses by tiling things wherever possible. Once they are able to make close guesses,
this work can be further extended by asking them to guess the area in terms of square cm.
‘ ’
MyBeltisLongest!
This triangle
is half of the
cm square
148 149
Reprint 2024-25
This Guess and check activity can be done in the class by making use of other things
present. For example: how many postcards can be placed on the top of the mathematics
book, how many charts will cover the classroom walls, etc? Children can be asked to check
their guesses by tiling things wherever possible. Once they are able to make close guesses,
this work can be further extended by asking them to guess the area in terms of square cm.
Whose card Length Width Perimeter Area
Sanya 10 cm 8 cm
Manav 11 cm 44 cm
Aarushi 8cm 80 square cm
Kabir 40 cm 100 square cm
MyBeltisLongest!
h
h
Take a thick paper sheet of length 14 cm and width 9 cm. You
can also use an old postcard.
What is its area? What is its perimeter?
Now cut strips of equal sizes out of it.
f ) Sanya, Aarushi, Manav and Kabir made greeting
cards. Complete the table for their cards:
h Make your own designs of area 4 and 6 square cm.
d) A square carrom board has a perimeter of 320 cm.
How much is itsarea?
e) How many tiles like the triangle given here will fit
in the white design?
Area of design = ________ square cm
This triangle
is half of the
cm square
148 149
Reprint 2024-25
Page 5
Area and its Boundary
Both could not make out whose
piecewasbigger.
Suggest some ways to find out
whosepieceisbigger.Discuss.
A friend of Parth and Gini showed
oneway,usingsmallsquares.
h
WhoseSliceisBigger?
ParthandGinibought (dried
mangoslice)fromashop.
Theirpieceslookedlikethese.
aampaapad
6 cm
5 cm
Piece A
Piece B
11 cm
3 cm
ThelengthofpieceAis6cm.
So6squaresofside1cmcanbearrangedalongitslength.
ThewidthofpieceAis5cm.
So5squarescanbearrangedalongitswidth.
11
CoverwithStamps
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
India 25
146 147
Reprint 2024-25
h Altogether how many squares can be arranged on it? ________
h So the area of piece A = ________ square cm
h In the same way find the area of piece B.
h Who had the bigger piece? How much bigger?
Cover with Stamps
This stamp has an area of 4 square cm. Guess how many such
stamps will cover this big rectangle.
It's silly to
count them all!
Just multiply!
Encourage children to first discuss different strategies for comparing the area of things by
using different tokens, stamps, etc. In Class IV they have compared irregular shapes by
counting squares. In the case of rectangles they can measure the sides to see how many
squares of 1 cm side will fit in the whole shape.
Piece A
Hkkjr India 25
147
Reprint 2024-25
Checkyourguess
a) Measure the yellow rectangle. It is ________ cm long.
b) How many stamps can be placed along its length? ________
c) How wide is the rectangle? ________ cm
d) How many stamps can be placed along its width? ________
e) How many stamps are needed to cover the rectangle? ________
f) How close was your earlier guess? Discuss.
g) What is the area of the rectangle? ________ square cm
h) What is the perimeter of the rectangle? ________ cm
Practicetime
a) Arbaz plans to tile his kitchen floor with
green square tiles. Each side of the tile is 10
cm. His kitchen is 220 cm in length and 180
cm wide. How many tiles will he need?
b) The fencing of a square garden is 20 m in length. How long is
one side of the garden?
c) A thin wire 20 centimetres long is formed into a
rectangle. If the width of this rectangle is
4 centimetres, what is its length?
This Guess and check activity can be done in the class by making use of other things
present. For example: how many postcards can be placed on the top of the mathematics
book, how many charts will cover the classroom walls, etc? Children can be asked to check
their guesses by tiling things wherever possible. Once they are able to make close guesses,
this work can be further extended by asking them to guess the area in terms of square cm.
‘ ’
MyBeltisLongest!
This triangle
is half of the
cm square
148 149
Reprint 2024-25
This Guess and check activity can be done in the class by making use of other things
present. For example: how many postcards can be placed on the top of the mathematics
book, how many charts will cover the classroom walls, etc? Children can be asked to check
their guesses by tiling things wherever possible. Once they are able to make close guesses,
this work can be further extended by asking them to guess the area in terms of square cm.
Whose card Length Width Perimeter Area
Sanya 10 cm 8 cm
Manav 11 cm 44 cm
Aarushi 8cm 80 square cm
Kabir 40 cm 100 square cm
MyBeltisLongest!
h
h
Take a thick paper sheet of length 14 cm and width 9 cm. You
can also use an old postcard.
What is its area? What is its perimeter?
Now cut strips of equal sizes out of it.
f ) Sanya, Aarushi, Manav and Kabir made greeting
cards. Complete the table for their cards:
h Make your own designs of area 4 and 6 square cm.
d) A square carrom board has a perimeter of 320 cm.
How much is itsarea?
e) How many tiles like the triangle given here will fit
in the white design?
Area of design = ________ square cm
This triangle
is half of the
cm square
148 149
Reprint 2024-25
The aim of the belt activity is to understand that things with the same area can take different
forms and also have very different perimeters. While measuring sides, lengths in mm can be
rounded off for this activity.
This belt is for
the elephant.
Look! I can pass through a
postcard. I made a loop
without cutting the strips.
Using tape join the strips, end to
end, to make a belt.
How long is your belt?_____
What is its perimeter _____
Whose belt is the longest in the
class?_____
Why did some of your friends get longer belts than others?
Is the area of your belt the same as the area of the postcard?
Why or why not?
What will you do to get a longer belt next time?
Discuss
h
h
h
h
h
h
With four Math-Magic
books in a line you can
get the length of around
one metre 9 cm.
PeoplePeopleEverywhere
150 151
Puzzle:PassthroughaPostcard
Can you think of how to cut a postcard
so that you can pass through it? (See
photo.) If you have tried hard enough
and still not got it… look for the answer
somewhere ahead.
Reprint 2024-25
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