The term perimeter refers to the coverage of the length of a figure from the outside. At the same time, the area is known as the object's surface. For different sets of figures, there are different formulas.
Different figures
Here, all different figures consist of different perimeters and areas. These are:
Square
The perimeter of the square is 4a, and its area is a^2.
Note: In the formula, a is the side of a square.
Rectangle
The rectangle's perimeter is 2 (l + b), and its area equals l x b.
Note: In the formula, l & b are the length and breadth of the square.
Circle
The circle's perimeter is 2πr, and its area is equal to πr^2.
Note: r is the radius of a circle, i.e., r = 2d (d = diameter)
Triangle
The triangle's area is equal to ½ x b x h.
Parallelogram
The parallelogram's area is b x h.
Units Conversion
To get the area and perimeter of a closed figure, we have to consider all figures in one unit. Only then do we have to apply the formula to get the results.
1 cm = 10 mm
1 m = 100 cm
1 km = 1000 m
1 hectare = 100 x 100 m
Learning Videos for 7th Grade Math - Perimeter and Area
The perimeters of a rectangle and a square is equal.
The length of the rectangle is 5 more than side of a square.The perimeter of square is 100 cm. What is breadth of the rectangle?
A. 25 cm
B. 30 cm
C. 20 cm
D. 15 cm
Question 2
In right angle triangle ABC, angle C is 90°, AC = 8 cm and AB is 10 m. What is area of the triangle ABC?
A. 20 cm²
B. 36 cm²
C. 40 cm²
D. 24 cm²
Question 3
The perimeter of an equilateral triangle is 36 m. Its height is 16 m. What is the area of the triangle?
A. 96 sq m
B. 84 sq m
C. 120 sq m
D. 106 sq m
Question 4
The length of the rectangle is thrice its breadth. The perimeter of a rectangle is 392 cm. What is its length?
A. 112 cm
B. 105 cm
C. 123 cm
D. 147 cm
Question 5
The area of a square is 50 cm². What is measure of its diagonal?