Question

two cross roads,each of width 10 m cut at right angles through the center of a rectangluar park of length 700 m and breath 300m parallel to its sides.Find the area of roads. and also find the area of the park excluding cross roads give the answer in hectares

Answer 1

Answer:

The area of roads is 0.99 hectares  and the area of the park excluding cross roads is 20.01 hectares.

Step-by-step explanation:

Here,

$PQ=10m , PS=300m, EH=10m ,\\ \\ EF=700m, KL=10m ,KN=10m$

Area of roads = Area of PQRS +Area of EFGH−Area of KLMN

[∵ KLMN is taken twice, which is to be subtracted]

               $=PS\cdot PQ+EF\cdot EH-KL\cdot KN\\ \\ =(300\cdot 10)+(700\cdot 10)-(10\cdot 10)\\ \\ =3000+7000-100\\ \\ =9,900m ^2$

Area of road in hectares,

               $1m ^2 = \frac{1}{10000} hectares\\ \\ 9900 m^2=\frac{9900}{10000}= 0.99 hectares$

Now, Area of park excluding cross roads = Area of park−Area of road

           $=(AB\cdot AD)-9,900\\ \\ =(700\cdot 300)-9,900\\ \\ =2,10,000-9,900\\ \\ =2,00,100 m ^2$

            $=\frac{200100}{10000}=20.01 hectares.$                

Answer 2

Answer: area of roads is 0.99 hectares and area of park excluding roads is 20.01 hectares

Step-by-step explanation:

Length of each portion = (700-10) /2 = 345 m

Width of each portion = (300-10) /2 = 145 m

Area of each portion = 345×145 =50025 sq m

Area without the roads = 4×50025 = 200100 sq m = 20.01 hectares

Total area of park = 700×300=210000 sq m = 21 hectares

Area of roads = 21-20.01 = 0.99 hectares