Steps: 2 Marks
Formula: 1 Mark
Answer: 1 Mark
The perimeter of an equilateral triangle:
= 3 $\times$ length of a side.
 

The total distance to be painted:
= 3 $\times$ 4 = 12 km        
 

$\Rightarrow$ Hence, the total cost for painting:
= 250 $\times$ 12
= Rs 3000
$\Rightarrow$ Area of the garden
= $\frac{1}{2}\times$ base $\times$ height.
= $\frac{1}{2}\times \frac{4}{2}\times 3.46$
= 3.46 km${}^2$

Steps: 2 Marks
Answer: 1 Mark

Perimeter of the figure will be:

= 3 cm + 6 cm + 3 cm + 3 cm + 10 cm + 3 cm + 2 cm + 3 cm + 2 cm + 3 cm 
(Starting from the topmost edge and going clockwise)
$=38cm$

Steps: 2 Marks
Formula: 1 Mark
Answer: 1 Mark
The area of the figure can be calculated in three steps:

i) Find the area of the small rectangle.

ii) Find the area of the large rectangle.

iii) Find the area of the triangle

i) Area of the small rectangle:
= length $\times$ breadth
= 5 $\times$ 6
= 30 inches${}^2$
 

ii) Area of the large rectangle:
= 12 $\times$ 4
= 48 inches${}^2$
 

iii) Area of the triangle:
= $\frac{1}{2}\times$ (height $\times$ base)
= $\frac{1}{2}\times$ 4 $\times$ 3 = 6 inches${}^2$

Area of the shape = Area of the small rectangle + Area of the large rectangle + Area of the triangle
= (30 + 48 + 6) inches${}^2$= 84 inches${}^2$

Each Option: 2 Marks
(a) Area of a rectangular garden:
= length $\times$ breadth = 18
= 3 $\times$ breadth

$\Rightarrow$ breadth = $\frac{18}{3}$
= 6 m
(b) Perimeter = 2 $\times$ (length + breadth)
= 2 $\times$ (3+6) = 18m${}^2$

The given figure has two parts, the lower part is a triangle and the upper part is a pentagon.

Given figure is an irregular figure, for which the number of sides cannot be found out. The figure is also a closed one.

The given figure has a total of 12 sides (AB, BC, CD, DE, EF, FG, GH, HI, IJ, JK, KL and LA). In order to complete a full round, one should reach the same corner one started from. So, we have to cover 12 sides.

The perimeter is the total length of the boundary of the closed figure. For a square, it is basically the sum of all the sides and in a square, all sides are equal. So, the perimeter is 4 x sides.

The sum of all the sides of a closed figure is termed its perimeter.