Volume, Surface Area and Solid Figures Tips and Tricks for Government Exams

Tips and Tricks and Shortcuts on Perimeter Area Volume

Here are rapid and straightforward tips and tricks for you on Perimeter, Area, and Volume. Acquire insights into the tricks and concepts related to Perimeter, area, and volume.

Clear all your SSC CGL doubts with EduRev Join for Free

Join for Free

Type 1: Find the area, perimeter, length, breadth and some other sides of the shapes

Example 1: The ratio between the length and the breadth of a rectangular plot is 7:3. Rahul was cycling along the boundary of the plot at a speed of 10 km/hr. He completes one round of the plot in 6 minutes. Find the area of the plot?
(a) 52000 m²
(b) 51500 m²
(c) 53500 m²
(d) 52500 m²
Ans: (d)
Distance covered by Rahul in 6 minutes =
Therefore, perimeter = 1000m
Length = 7x and breadth = 3x
Then 2 (l +b) = 1000
2 (7x + 3x) = 1000
2 (10x) = 1000
20x = 1000
x = 50
Length = 7x = 7 * 50 = 350
Breadth = 3x = 3 * 50 = 150
Therefore, Area = l * b = 350 * 150 = 52500 m²

Type 2: Perimeter, Area and Volume Tips and Tricks and Shortcuts by finding the volume & surface area

Example 1:What is the total surface area of a right circular cone of height 10 cm and base radius 7 cm?
(a) 422.4 m²
(b) 422.4 cm²
(c) 422.4 cm³
(d) 422.4 cm
Ans:(b)
h = 10 cm, r = 7 cm


Total surface area of cone = πrl + πr²

268.4 + 154
422.4 cm²

Download the notes Tips and Tricks: Volume, Surface Area & Solid Figures

Download as PDF

Download as PDF

Type 3:Tips and Tricks and Shortcuts for Perimeter, Area and Volume by finding Percentage increase or decrease

Example 1:If length of the rectangle is increased by 50% and breadth is decreased by 20%. Then what is the percentage change in the area?
(a) 70% decrease
(b) 30 % increase
(c) 20% increase
(d) 20% decrease
Ans:(c)
Original area = l * b
New length = 50% increase

New breadth = 20% decrease
Therefore, new area
New area
Change in Area = New Area – Original Area
Change in Area
Change in Area

Percentage change in area
Percentage change in area
Since, the answer is positive, it means there is increase in the area.

Take a Practice Test Test yourself on topics from SSC CGL exam

Practice Now

Practice Now

Type 4: How to solve cost related problems

Example 1:A wall of trapezium shape has height 8 m. The parallel sides of trapezium are 4 m and 6 m. If the rate of painting per square meter is Rs.50 than find the cost painting the complete wall?
(a) Rs. 4000
(b) Rs. 4200
(c) Rs. 5400
(d) Rs. 2000
Ans:(d)

Step 1: Area of a Trapezium: The formula for the area of a trapezium is:
Area = (1/2) × (Sum of parallel sides) × Height
Here:
Parallel sides: 4 m and 6 m
Height: 8 m
Substituting the values:
Area = (1/2) × (4 + 6) × 8
Area = (1/2) × 10 × 8
Area = 40 m²

Step 2: Cost of Painting
The rate of painting is Rs. 50 per square meter. The total cost is:
Cost = Area × Rate
Cost = 40 × 50 = Rs. 2000

The cost of painting the complete wall is Rs. 2000.