Question

the ratio of the length to breadth of a lawn is 3:5. it costs ??? 3200 to fence it at the rate of ??? 2 a metre. what would be the cost of developing the lawn at the rate of ???10 per square metre.

Answer 1

let the length to breadth be 3x and 5x
fencing means perimeter
now
total fenced part =3200/2= 1600
perimeter of rectangle =2*l+b
1600=2*3x+5x
1600=2*8x
1600=16x
x=1600/16=100
now x= 100
as given
l=3x
=3*100=300
b=5x
=5*100=500
then
area=l*b
=300*500
=150000
now
developing the lawn =150000*10=1500000