CBSE Class 8 Maths MCQs on Area of Composite Figures and Practical Problems
CBSE Class 8 Maths MCQs on Area of Composite Figures and Practical Problems
Class: 8 | Subject: Mathematics | Chapter 14: Area (Mensuration & Composite Figures)
These MCQs are strictly designed as per the CBSE curriculum based on NCERT textbooks and are ideal for CBSE Class 8 Mathematics examinations.
1. A composite figure is formed by:
Correct Answer: B
Composite figures are made by joining basic shapes like rectangles, triangles, semicircles etc.
Composite figures are made by joining basic shapes like rectangles, triangles, semicircles etc.
2. A rectangle 25 m × 10 m has a triangular section (base 10 m, height 8 m). Total area:
Correct Answer: B
Rectangle = 25×10 = 250 m²
Triangle = ½×10×8 = 40 m²
Total = 250 + 40 = 290 m².
Rectangle = 25×10 = 250 m²
Triangle = ½×10×8 = 40 m²
Total = 250 + 40 = 290 m².
3. To calculate area of composite figures, we generally:
Correct Answer: B
Break the figure into known shapes, calculate individual areas, then add or subtract accordingly.
Break the figure into known shapes, calculate individual areas, then add or subtract accordingly.
4. A 12 m × 8 m rectangular floor has a 4 m × 2 m rectangular pit removed. Remaining area:
Correct Answer: B
Big rectangle = 96 m²
Pit area = 8 m²
Remaining = 96 − 8 = 88 m².
Big rectangle = 96 m²
Pit area = 8 m²
Remaining = 96 − 8 = 88 m².
5. A square park (side 20 m) has a triangular lawn (base 20 m, height 10 m). Total area:
Correct Answer: B
Square = 20² = 400 m²
Triangle = ½×20×10 = 100 m²
Total = 500 m².
Square = 20² = 400 m²
Triangle = ½×20×10 = 100 m²
Total = 500 m².
6. Area of triangle with base 16 cm and height 5 cm:
Correct Answer: A
Area = ½×16×5 = 40 cm².
Area = ½×16×5 = 40 cm².
7. A rectangular garden 30 m × 12 m is divided into two equal triangles. Area of one triangle:
Correct Answer: A
Rectangle area = 360 m²
Each triangle = 360 ÷ 2 = 180 m².
Rectangle area = 360 m²
Each triangle = 360 ÷ 2 = 180 m².
8. A 10 m × 6 m rectangle is attached to a 6 m × 6 m square. Total area:
Correct Answer: A
Rectangle = 60 m²
Square = 36 m²
Total = 96 m².
Rectangle = 60 m²
Square = 36 m²
Total = 96 m².
9. A figure consists of two rectangles of areas 40 m² and 60 m². Combined area:
Correct Answer: A
Add both areas: 40 + 60 = 100 m².
Add both areas: 40 + 60 = 100 m².
10. A composite figure has area 150 m². If one part is 50 m², remaining area:
Correct Answer: A
Remaining = 150 − 50 = 100 m².
Remaining = 150 − 50 = 100 m².
11. A rectangular floor 24 m × 15 m has a triangular platform (base 15 m, height 8 m). Total area is:
Correct Answer: A
Rectangle area = 24 × 15 = 360 m²
Triangle area = ½ × 15 × 8 = 60 m²
Total = 360 + 60 = 420 m².
Rectangle area = 24 × 15 = 360 m²
Triangle area = ½ × 15 × 8 = 60 m²
Total = 360 + 60 = 420 m².
12. A square of side 14 m is joined to a rectangle 14 m × 6 m. Combined area:
Correct Answer: A
Square = 14² = 196 m²
Rectangle = 14 × 6 = 84 m²
Total = 196 + 84 = 280 m².
Square = 14² = 196 m²
Rectangle = 14 × 6 = 84 m²
Total = 196 + 84 = 280 m².
13. A 20 m × 12 m rectangular field has a 4 m × 3 m pit removed. Remaining area:
Correct Answer: A
Field area = 20 × 12 = 240 m²
Pit area = 4 × 3 = 12 m²
Remaining = 240 − 12 = 228 m².
Field area = 20 × 12 = 240 m²
Pit area = 4 × 3 = 12 m²
Remaining = 240 − 12 = 228 m².
14. A composite figure consists of two triangles each of area 35 m². Total area:
Correct Answer: A
Total area = 35 + 35 = 70 m².
Total area = 35 + 35 = 70 m².
15. A rectangular wall 18 m × 10 m has a square window 4 m side. Area to be painted:
Correct Answer: A
Wall = 18 × 10 = 180 m²
Window = 4² = 16 m²
Paint area = 180 − 16 = 164 m².
Wall = 18 × 10 = 180 m²
Window = 4² = 16 m²
Paint area = 180 − 16 = 164 m².
16. A rectangular garden 40 m × 25 m has a triangular section (base 25 m, height 10 m). Total area:
Correct Answer: A
Rectangle = 40 × 25 = 1000 m²
Triangle = ½ × 25 × 10 = 125 m²
Total = 1125 m².
Rectangle = 40 × 25 = 1000 m²
Triangle = ½ × 25 × 10 = 125 m²
Total = 1125 m².
17. A composite figure is made of three rectangles of areas 50 m², 30 m² and 20 m². Combined area:
Correct Answer: A
Add all areas: 50 + 30 + 20 = 100 m².
Add all areas: 50 + 30 + 20 = 100 m².
18. A 16 m × 12 m rectangle is divided diagonally into two triangles. Area of one triangle:
Correct Answer: A
Rectangle area = 16 × 12 = 192 m²
Each triangle = 192 ÷ 2 = 96 m².
Rectangle area = 16 × 12 = 192 m²
Each triangle = 192 ÷ 2 = 96 m².
19. A 30 m × 20 m field has a 10 m × 5 m rectangular shed. Remaining area:
Correct Answer: A
Field = 30 × 20 = 600 m²
Shed = 10 × 5 = 50 m²
Remaining = 600 − 50 = 550 m².
Field = 30 × 20 = 600 m²
Shed = 10 × 5 = 50 m²
Remaining = 600 − 50 = 550 m².
20. A composite field consists of a rectangle 18 m × 12 m and a triangle (base 12 m, height 9 m). Total area:
Correct Answer: A
Rectangle = 18 × 12 = 216 m²
Triangle = ½ × 12 × 9 = 54 m²
Total = 216 + 54 = 270 m².
Rectangle = 18 × 12 = 216 m²
Triangle = ½ × 12 × 9 = 54 m²
Total = 216 + 54 = 270 m².