CG SCERT (Chhattisgarh Board) Class 8 Mathematics Solutions | 2026-27 Official Edition
Complete 100% textbook-grounded CG Board Class 8 Mathematics Chapter 14 Solutions: Mensuration-I (क्षेत्रमिति-1) in Bilingual Format (English & Hindi Medium).
Area = 1/2 × d1 × d2 or Area = Base × Height
Area of Path = Outer Rectangle Area – Inner Rectangle Area
Area of Path = π (R2 – r2)
Find out the area of a parallelogram whose…
Find out the area of a parallelogram whose…
(i) Base = 15 cm, Height = 10 cm**
Area = Base × Height = 15 × 10 = 150 cm2
(ii) Base = 90 cm, Height = 8 cm
Area = 90 × 8 = 720 cm2
(iii) Base = 120 cm, Height = 15 cm
Area = 120 × 15 = 1800 cm2
Find the area of the parallelogram where base…
Find the area of the parallelogram where base…
Area = Base × Height = 26.5 × 7 = 185.5 cm2
Find out the base of the parallelogram whose…
Find out the base of the parallelogram whose…
Base = (Area)/(Height) = 390/26 = 15 cm
Find out the perpendicular of parallelogram with area…
Find out the perpendicular of parallelogram with area…
Height = (Area)/(Base) = (1200)/(60) = 20 m
Find out the area of a triangle with…
Find out the area of a triangle with…
Area = 1/2 × Base × Height = 1/2 × 12 × 7 = 42 cm2
Find out the area of a triangle with…
Find out the area of a triangle with…
Area = 1/2 × 25 × 1.5 = (37.5)/(2) = 18.75 cm2
Find out the perpendicular length of a triangle…
Find out the perpendicular length of a triangle…
Height = (2 × Area)/(Base) = (2 × 26)/(6.5) = 52/6.5 = 8 cm
Find out the area of a triangle where…
Find out the area of a triangle where…
Area = 1/2 × 120 × 75 = 60 × 75 = 4500 dm2
Find the area of a rhombus where diagonals…
Find the area of a rhombus where diagonals…
Area = 1/2 × d1 × d2 = 1/2 × 24 × 10 = 120 cm2
Find the area of a rhombus where one…
Find the area of a rhombus where one…
Since a rhombus is also a parallelogram
Area = Base × Height = 7.5 × 4 = 30 cm2
Find the area of a trapezium where parallel…
Find the area of a trapezium where parallel…
Area = 1/2 × (b1 + b2) × h = 1/2 × (20 + 8) × 12 = 14 × 12 = 168 m2
What will be the area of the trapezium…
What will be the area of the trapezium…
Area = 1/2 × (30 + 24.4) × 1.5 = 1/2 × 54.4 × 1.5 = 27.2 × 1.5 = 40.8 cm2
The area of a trapezium is 105 cm²…
The area of a trapezium is 105 cm…
Let the smaller parallel side = x cm.
- Then the other parallel side = (x + 6) cm.
- Formula
Area = 1/2 × (b1 + b2) × h
105 = 1/2 × (x + x + 6) × 7
105 × 2 = (2x + 6) × 7
210 = (2x + 6) × 7 ⇒ 2x + 6 = 210/7 = 30
2x = 30 – 6 = 24 ⇒ x = 12 cm
- Parallel sides are 12 cm and 12 + 6 = 18 cm.
A 25 cm long and 10 cm wide…
A 25 cm long and 10 cm wide…
Dimensions of picture (Inner rectangle): Length = 25 cm, Width = 10 cm.
Inner Area = 25 × 10 = 250 cm2
- Dimensions with frame (Outer rectangle)
Outer Length = 25 + 2 + 2 = 29 cm
Outer Width = 10 + 2 + 2 = 14 cm
Outer Area = 29 × 14 = 406 cm2
- Area of frame = 406 – 250 = 156 cm2.
A rectangular playground measures 35 m 25 m…
A rectangular playground measures 35 m 25 m…
Area of road parallel to length = 35 × 3 = 105 m2.
- Area of road parallel to width = 25 × 2 = 50 m2.
- Area of common central intersection = 3 × 2 = 6 m2.
- Total Area of road = 105 + 50 – 6 = 149 m2.
A basketball ground is 28 m long and…
A basketball ground is 28 m long and…
Inner Area (Ground) = 28 × 15 = 420 m2.
- Outer Length = 28 + 5 + 5 = 38 m.
Outer Width = 15 + 5 + 5 = 25 m.
Outer Area = 38 × 25 = 950 m2.
- Area of Gallery = 950 – 420 = 530 m2.
- Cost of construction = 530 × 5.25 = Rs. 2782.50.
The radius of two concentric circles are 9…
The radius of two concentric circles are 9…
Given: R = 12 cm, r = 9 cm.
- Area of circular path
Area = π (R2 – r2) = 22/7 (122 – 92) = 22/7 (144 – 81) = 22/7 × 63 = 22 × 9 = 198 cm2
The area of a circle is 616 cm²…
The area of a circle is 616 cm…
Area of inner circle = π r2 = 616 m2 (taking units as meters)
22/7 × r2 = 616 ⇒ r2 = (616 × 7)/(22) = 28 × 7 = 196 ⇒ r = 14 m
- Outer radius R = 14 + 2 = 16 m.
- Area of outer circle
Outer Area = 22/7 × 162 = (22 × 256)/(7) = (5632)/(7) ≈ 804.57 m2
- Area of road = 804.57 – 616 = 188.57 m2.
The radius of a circular cricket ground is…
The radius of a circular cricket ground is…
Given: Inner radius r = 60 m, width of gallery = 7 m.
- Outer radius R = 60 + 7 = 67 m.
- Area of spectator gallery
Area = π (R2 – r2) = 22/7 (672 – 602) = 22/7 (67 + 60)(67 – 60)
Area = 22/7 × 127 × 7 = 22 × 127 = 2794 m2