Symmetry | FIO

Question 3

Punching Game

The fold is a line of symmetry. Punch holes at different locations of a folded square sheet of paper using a punching machine and create different symmetric patterns.

Question diagram 1
Check your answer with HomiSolve it yourself, then let Homi check your steps and spot mistakes.
Solution
Understand the Question
  • Folding a paper in half forms a crease that acts as the line of symmetry (mirror line).
  • Punching a hole through the folded layers penetrates multiple layers at the same relative position.
  • When unfolded, each punch produces symmetric pairs of holes positioned at equal distances on opposite sides of the fold line.

Step 1 · Fold the Paper

Take a square sheet of paper and fold it in half. The crease formed represents the line of symmetry.Diagram 1

Step 2 · Punch a Hole

Punch a hole through the folded paper using a hole punch. The punch goes through both overlapping layers.Diagram 2

Step 3 · Unfold to Reveal the Symmetric Pattern

Unfold the sheet of paper. Two holes are visible, each positioned as a mirror image of the other across the central fold line.Diagram 3

Answer

The fold line serves as the line of symmetry, resulting in a symmetric pattern where holes are equidistant and mirrored across the crease.

Common Mistakes
  • Punching on the Fold Line: Punching directly on the crease produces only one centered hole instead of two symmetric holes.
  • Number of Holes: Forgetting that punching through nn folded layers produces nn distinct holes upon unfolding.

More questions in FIO

Q1

Do you see any line of symmetry in the figures at the start of the chapter? What about in the picture of the cloud?

Q2

For each of the following figures, identify the line(s) of symmetry if it exists.

Q3

Punching Game

The fold is a line of symmetry. Punch holes at different locations of a folded square sheet of paper using a punching machine and create different symmetric patterns.

Q4

In each of the following figures, a hole was punched in a folded square sheet of paper and then the paper was unfolded. Identify the line along which the paper was folded. Figure (d) was created by punching a single hole. How was the paper folded?

Q5

Given the line(s) of symmetry, find the other hole(s):

Q6

Here are some questions on paper cutting. Consider a vertical fold. We represent it this way:

Vertical Fold

Similarly, a horizontal fold is represented as follows:

Horizontal Fold

Q7

After each of the following cuts, predict the shape of the hole when the paper is opened. After you have made your prediction, make the cutouts and verify your answer.

Q8

Trace each figure and draw the lines of symmetry, if any:

Q9

Copy the following on a dot grid. For each figure draw two more lines to make a shape that has a line of symmetry.

Q10

Find the angles of symmetry for the given figures about the point marked •.

(a) (b) (c)

Q11

Which of the following figures have more than one angle of symmetry?

Q12

Give the order of rotational symmetry for each figure:

Q13

Colour the sectors of the circle below so that the figure has:

(i) 3 angles of symmetry

(ii) 4 angles of symmetry

(iii) What are the possible numbers of angles of symmetry you can obtain by colouring the sectors in different ways?

Q14

Draw two figures other than a circle and a square that have both reflection symmetry and rotational symmetry.

Q15

Draw, wherever possible, a rough sketch of:

a. A triangle with at least two lines of symmetry and at least two angles of symmetry.

b. A triangle with only one line of symmetry but not having rotational symmetry.

c. A quadrilateral with rotational symmetry but no reflection symmetry.

d. A quadrilateral with reflection symmetry but not having rotational symmetry.

Q16

In a figure, 6060^\circ is the smallest angle of symmetry. What are the other angles of symmetry of this figure?

Q17

In a figure, 6060^\circ is an angle of symmetry. The figure has two angles of symmetry less than 6060^\circ. What is its smallest angle of symmetry?

Q18

Can we have a figure with rotational symmetry whose smallest angle of symmetry is:

a. 4545^\circ?

b. 1717^\circ?

← Back to Symmetry