Question

5. Two cross roads, each of width 10 m, cut at right angles through the centre of a
rectangular park of length 700 m and breadth 300 m and parallel to its sides. Find the
area of the roads. Also find the area of the park excluding cross roads. Give the
answer in hectares.
​

Answer 1

Answer:

Here, PQ=10m and PS=300m, EH=10m and EF=700m

And KL=10m and KN=10m

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

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

=PS×PQ+EF×EH−KL×KN

=(300×10)+(700×10)−(10×10)

=3000+7000−100

=9,900m

2

Area of road in hectares, 1m

2

=

10000

1

hectares

∴9,900m

2

=

10000

9900

=0.99 hectares

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

=(AB×AD)−9,900

=(700×300)−9,900

=2,10,000−9,900

=2,00,100 m

2

=

10000

200100

hectares=20.01 hectares.