๐ท Chapter 3 โ How Many Squares?
Subject: Mathematics
Main Concepts: Area, Perimeter, Squares, Rectangles, Comparing Areas
๐ Introduction
In this chapter, we learn how to compare sizes of shapes using squares. We also understand two very important ideas: Area and Perimeter.
Children are not required to memorise formulas here. Instead, they learn by counting squares, observing shapes, and doing activities.
โฌ What is a Square Grid?
A square grid is made of many equal squares. Each small square usually has a side of 1 cm.
๐ What is Area?
Area tells us how much surface a shape covers.
โ How to find Area using squares
To find area:
- Place the shape on a square grid
- Count the number of full squares covered
If a shape covers 12 small squares, its area = 12 square cm
๐ What is Perimeter?
The length of the boundary of a shape is called its perimeter.
๐ฅ Rectangles with Same Area
If we use 12 equal squares, we can make many rectangles.
| Rectangle Size | Area | Perimeter |
|---|---|---|
| 1 ร 12 | 12 sq cm | 26 cm |
| 2 ร 6 | 12 sq cm | 16 cm |
| 3 ร 4 | 12 sq cm | 14 cm |
โ Perimeter changes
๐ฎ Measuring Area using Stamps
We can find the area of stamps by placing them on a square grid.
If a stamp covers 12 squares, Area of the stamp = 12 sq cm
๐ฃ How Big is My Hand or Foot?
Hands and footprints have irregular shapes. To find their area:
- Trace the hand or foot on squared paper
- Count full squares
- Join half squares to make full squares
Trace your hand and your friendโs hand. Count the squares and compare the areas.
๐พ Animal Footprints
Different animals have footprints of different areas.
โ Shape may be different but area can be same
๐บ Try Triangles
A triangle can be formed by cutting a rectangle into two equal parts.
โ๏ธ Complete the Shape
Sometimes only part of a shape is drawn. We complete it so that the area becomes a given value.
Can different shapes have the same area? โ Yes!
๐งฉ Puzzles with Five Squares
Using 5 equal squares, many different shapes can be made.
โ Perimeter may be different
๐ฎ Game Time & Tiling
Some shapes can cover a floor completely without gaps. This is called tiling.
โ Some shapes do not tile
โ๏ธ Practice Questions
2) Can two shapes have the same area but different perimeters?
3) How do you find the area of an irregular shape?
4) If a rectangle has area 20 sq cm, what is the area of one half?
โ Quick Revision
โ Perimeter is the boundary length
โ Same area โ same perimeter
โ Counting squares helps find area
๐ Chapter Complete
After studying this chapter, students can confidently compare areas, understand perimeters, and solve puzzles using squares.
๐ Complete Worksheet โ How Many Squares?
Chapter: How Many Squares?
Focus: Area, Perimeter, Squares, Rectangles ๐ฏ
Section A โ Multiple Choice Questions (MCQs)
Q1. The length of the boundary of a shape is called:
Q2. If a shape covers 15 small squares, its area is:
Q3. Two rectangles made of 12 equal squares will always have:
Q4. Which unit is used to measure area?
โ Q2 โ (b) 15 square cm
โ Q3 โ (c) Same area
โ Q4 โ (c) square cm
Section B โ Fill in the Blanks
2) A square grid helps us to find __________ of a shape.
3) Two shapes can have the same area but different __________.
4) Each small square in a grid usually represents __________ square cm.
โ area
โ perimeter
โ 1
Section C โ Very Short Answer Questions
1) What does area tell us?
2) What is perimeter?
3) Name the shape that tiles a floor easily.
โ Perimeter is the length of the boundary of a shape.
โ Square / Rectangle
Section D โ Short Answer Questions
Q1. How do you find the area of an irregular shape?
Q2. Can two shapes have the same area but different perimeters? Explain.
Q3. A rectangle covers 20 squares. What is its area?
โ Yes, area can be same but boundary length can be different.
โ 20 square cm
Section E โ Long Answer Questions
Q1. Explain with an example how rectangles of the same area can have different perimeters.
Q2. How will you find the area of your hand?
โ Trace hand on grid, count full and half squares.
Section F โ HOTS / Thinking Questions โญ
Q1. Why do squares with the same area sometimes look different?
Q2. Why are square tiles commonly used on floors?
โ They tile the floor completely without gaps.
๐ฏ Worksheet Complete
โ Practice grid counting daily
โ Revise area vs perimeter difference
โ You are now exam-ready โ