CLASS-4
AREA - PROBLEM & SOLUTION 

Formulae of Area is described below -

1.) Area of a rectangle = Length x Breadth = L X W

2.) Area of a square = Side x Side = S X S

                                    Area

3.) Length of a rectangle = ------------

                                  Breadth

                                     Area

4.) Breadth of a rectangle = ------------

                                    Length

Please Note -

While calculating area of a rectangle, we must express its length and breadth in the same units.

Always express area in square units.

There are some examples are given below for your better understanding -

Example.1) A rectangle is 39 cm long and 24 cm 5 mm wide. Find its area.

Ans.) Length of the rectangle = 39 cm = 390 mm

Breadth of the rectangle = 24 cm 5 mm = 245 mm

∴ Area of the rectangle = Length x Breadth

                           = 390 mm x 245 mm

                           = 95550 sq mm

Ans: The area of the rectangle is 95,550 sq mm.   (Ans.)

Example.2)  The side of a square playground is 125 m.

              i)  Find the area of the playground.

              ii) Find the cost of levelling it at the rate of rupees 7 per sq m.

Ans.)

(i)  Length of the side of a square playground = 125 m

∴ Area of the square playground = side x side

                                    = 125 m x 125 m

                                    = 15,625 sq m

The area of the square playground is 15,625 sq m.   (Ans.)

(ii)  Cost of levelling 1 sq m of the playground = 7 rupees

∴ Cost of levelling 15,625 sq m of the playground = Area x 7 rupees

                                                       = 15,625 x 7

                                                       = 1,09,375 rupees

The cost of levelling the playground at the rate of rupees 7 per sq m is Rupees 1,09,375.   (Ans.)