NCERT Solutions for Class 4th Maths Chapter 11 Fun with Symmetry
Updated on 2026-09-19
About this chapter
A shape is symmetrical if a fold makes its two halves sit exactly on each other. That fold is its line of symmetry . A shape may have 0, 1, 2 or more lines of symmetry. A square has 4, a rectangle has 2, a parallelogram has none. A mirror kept on a line shows one half and its reflection together. The line is called the mirror line or line of reflection . Letters and digits have their own symmetry. The digits 0, 1 and 8 look the same in a mirror kept at the side. Folding and cutting paper gives symmetrical holes. Every fold doubles the number of cuts you get. Tiles are laid with no gaps and no overlaps. The same tile can be slid, flipped or turned to make a pattern.
- . Ink Design
- . Making a paper airplane
- . Holes and Cuts
- . Complete the designs below
- Symmetry in shapes
- . Games with a Mirror
- . Letters on the ambulance
- . Observe the shapes
- Patterns with tiles
- Bablu Chacha’s tiles
Quick revision
| Shape | Number of sides | Lines of symmetry | Where the line goes |
|---|---|---|---|
| Square | 4 | 4 | 2 through the middle, 2 along the corners |
| Rectangle | 4 | 2 | One across the middle, one down the middle |
| Rhombus (diamond) | 4 | 2 | Along its two diagonals |
| Kite | 4 | 1 | Along its long diagonal |
| Isosceles trapezium | 4 | 1 | Straight down the middle |
| Parallelogram | 4 | 0 | It has none |
| Arrowhead (dart) | 4 | 1 | Down the middle, through the point |
| Isosceles triangle | 3 | 1 | From the tip to the middle of the base |
| Right isosceles triangle | 3 | 1 | From the square corner to the middle of the longest side |
| Scalene triangle | 3 | 0 | It has none |
| Digits 0, 1, 8 | — | yes | A mirror at the side leaves them the same |
| Digits 0, 1, 3, 8 | — | yes | A mirror above or below leaves them the same |
Exercises
- . Ink Design — Let Us Do Page 1641
- . Making a paper airplane — Let Us Do Page 1652
- . Holes and Cuts — Holes and Cuts Page 1663
- . Complete the designs below — In-text Questions Page 1674
- Symmetry in shapes — Let Us Do Page 167
- . Games with a Mirror — Games with a Mirror Page 1682
- . Letters on the ambulance — In-text Questions Page 1693
- . Observe the shapes — In-text Questions Page 1705
- Patterns with tiles — Tiling the Tiles Page 170
- Bablu Chacha’s tiles — Tiles at the Tile Shop Page 171
- . Look at the following shapes — In-text Questions Page 1724
- . Make floor patterns — Let Us Do Page 1721
- . Making a catty wall! — In-text Questions Page 1732
- . Let us go on a nature walk (Project time) — Project Work Page 1743