please explain experts (fig.11.1 in text book)

a rectangular park whose length is 30 m and width is 20 m.

(i) What is the total length of the fence surrounding it? To find the length of the fence we

need to find the perimeter of this park, which is 100 m.

(ii) How much land is occupied by the park? To find the

land occupied by this park we need to find the area of

this park which is 600 square meters (m2(How?).

(iii) There is a path of one metre width running inside along

the perimeter of the park that has to be cemented.

If 1 bag of cement is required to cement 4 m2

area, howmany bags of cement would be required to construct the

cemented path?

We can say that the number of cement bags used =area of the path

area cemented by 1 bag

.

Area of cemented path = Area of park – Area of park not cemented.

Path is 1 m wide, so the rectangular area not cemented is (30 – 2) × (20 – 2) m2

.

That is 28 × 18 m2

.

Hence number of cement bags used = ------------------

(iv) There are two rectangular flower beds of size 1.5 m × 2 m each in the park as

shown in the diagram (Fig 11.1) and the rest has grass on it. Find the area covered

by grass.

TRY THESE

Area of rectangular beds = ------------------

Area of park left after cementing the path = ------------------

Area covered by the grass = ------------------