Introduction
Chapter 20 deals with Mensuration I – Area of a Trapezium and a Polygon, a vital topic for calculating the area of various geometrical figures. This chapter teaches how to find areas of irregular shapes by dividing them into simple polygons.
Important Concepts Covered
Students learn how to:
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Derive and apply the formula for the area of a trapezium
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Calculate the area of polygons using decomposition
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Solve real-life problems involving land measurement and design
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Relate perimeter and area concepts for composite figures
The RD Sharma Class 8 Maths Solutions include clear steps and formulas for accurate calculations.
Formula Understanding
For a trapezium with parallel sides ‘a’ and ‘b’ and height ‘h’,
Area = ½ × (a + b) × h.
Students also learn how to apply similar approaches for pentagons and hexagons by breaking them into triangles and rectangles.
Application in Real Life
Mensuration is applied in architecture, carpentry, and land surveying. Understanding how to calculate areas helps students handle practical geometry-related problems with confidence.
Benefits of RD Sharma Solutions
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Simple and formula-based stepwise approach
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Real-world problem-solving examples
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Diagrams and clear labeling for better understanding
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Thorough practice exercises for exam preparation
Conclusion
Chapter 20 – Mensuration I gives students strong command over calculating areas of complex shapes. Regular practice of RD Sharma exercises helps improve speed and accuracy in mensuration problems.