Question

a rectangular lawn 80*60m has two roads each 10m wide running in the middle of it,one parallel to the length and the other parallel to the breadth.find the cost of graveling them at ₹1.20 per square metre

Answer 1

FOR RECTANGULAR LAWN.
Length, L = 80m.
Breadth, B= 60m.

For Vertical road:
length= Breadth of rectangle
length = 60m.

Breadth = 10m.

Thus, Area of vertical road
=length × breadth
= 60m ×10m
=600m².

For Horizontal road:
length = length of rectangle.
length = 80m
breadth= 10m.

Thus, area of horizontal road
= length ×breadth
= 800m × 10m
=800m².

Note: The roads overlap in the middle of rectangle and form a square having side of 10m.

FOR SQUARE:
Area of square = Side × Side
Area of square = 10m × 10m
Area of square = 100m².


Therefore,
Area needd of road to be gravel
= Area of vertical road + area of horizontal road - area of square

= 600m² + 800m² -100m²
= 1300m².

If the cost of gravelling for 1m² = Rs 1.20
So, Cost of gravelking for 1300m²
= 1300 ×Rs 1.20
=Rs 1,560. Ans.

Answer 2

Good