Class 6 Maths Chapter 6 Perimeter and Area Revision Notes

Perimeter and area might use similar-looking formulas in Chapter 6, but this recap also covers the grid method for estimating irregular areas and how the two measures can behave independently.

Last Updated: September 23, 2026

Perimeter Formulas

• Rectangle: 2 × (length + breadth)
• Square: 4 × side
• Regular polygon: number of sides × side length

Area Formulas

• Rectangle: length × breadth
• Square: side × side
• Triangle: ½ × base × height

Estimating Irregular Areas (Grid Method)

• Fully covered square = 1; more-than-half covered = 1; exactly half = ½; less-than-half = ignore (0).

Key Relationship: Perimeter vs Area

• Same perimeter can give different areas — among rectangles with a fixed perimeter, the one closest to a square has the greatest area.
• Same area can give different perimeters — among rectangles with a fixed area, the one closest to a square has the smallest perimeter; the most elongated rectangle has the largest.

Worked Answers Recap

• Area-24 rectangles: smallest perimeter = 4×6 (P=20); largest = 1×24 (P=50).
• Fencing 150m×120m field @ Rs.40/m = Rs.21,600.
• Tiling 500cm×200cm floor @ Rs.8/100sq.cm = Rs.8,000.

Quick revision:

• Revision Notes for Class 6 Maths Chapter 1: Patterns in Mathematics
• Class 6 Maths Chapter 2 Lines and Angles Revision Notes
• Class 6 Maths Chapter 3 Number Play Revision Notes
• Class 6 Maths Chapter 4 Data Handling and Presentation Revision Notes
• Class 6 Maths Chapter 5 Prime Time Revision Notes

Frequently Asked Questions

What is the difference between perimeter and area, and what units are used to measure each?
Perimeter is the total length around the boundary of a shape, measured in linear units like centimetres, while area is the amount of surface enclosed within that boundary, measured in square units.

Can two shapes have the same area but different perimeters?
Yes, two shapes can enclose the same amount of surface area while having boundaries of very different total lengths, such as a long thin rectangle compared to a more compact square of equal area.

Written by Satish

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