Question

The sides of a rectangular park are in the ratio 4:3. If the area is 1728 metre square, find the cost of fencing it at the rate of Rs. 2.50/m.

Answer 1

let the side of rectangular Park be 4x and 3x. Then,

Area of rectangular Park=l*b

1728 =4x*3x

1728 =12x2

1728÷12 =x2

144 =x2

square root of 144 =x

12 =x

Hence, length of rectangle=4x

= 4*12=48

Breadth of rectangle=3x

=3*12=36

Cost of fencing per m2=2.50

cost of fencing of 1728m2=

4320.

Answer 2

let the length of rectangle=4x

let the breadth of rectangle=3x

Area=1728m square

l*b=17284

4x*3x=1728

12x=1728

x=1728/12

x2=144
x=12
length=4x

=4*12

=48m

breadth=3x

=3*12

=36m

cost of fencing of RS.1m square=2.50m

cost of fencing RS.1728=RS.4320.00