Boundary is a border that encloses a space or an area.
The distance around the boundary is called as 'perimeter'.
The length of the three sides of a triangular field is 9 m, 5 m, and 11 m
The boundary or perimeter of the field is given as 9 m + 5 m + 11 m = 25 m
A. 75
B. 80
C. 70
D. 60
Correct Answer: B
Step 1: Perimeter of the quadrilateral ABCD = Sum of the four sides of the quadrilateral.
Step 2: = AB + BC + CD + DA
Step 3: = 3 + 8 + 4 + 5 = 20 meters [Substitute AB = 3, BC = 8, CD = 4, and DA = 5 and simplify.]
Step 4: The number of plants required = 20 × 4 = 80.