Question

A playground is 25 m long and 20 m wide . find the cost of fencing it at the rate of 2.50 per square metre​

Answer 1

Answer:

Given :

Total cost of fencing =Rs. 10080

Cost of fencing per meter =20

So perimeter =

20

10080

=504 m

So length of square =

4

504

=126 m

width of pavement =3 m

Length of inner square =126−3=120 m

So, area of pavement =Area of Outer square − Area of inner square

=126×126−120×120

Area of pavement=1476 m

2

Cost of pavement =1476×50

∴ Cost of pavement=Rs. 73800

Answer 2

$\sf \large \underbrace{ \underline{Understanding \: the \: Question}}$

The length and width of the rectangular playground are given and we have to find the cost of fencing. As we all know that fencing is always done on boundary so we have to find the perimeter of the rectangular field and multiply it by the cost per metre.

Let's start!

★Perimeter of rectangle=2(L+B)

[Where l and b are length and breadth respectively]

$\sf : \implies2(25 + 20)m$

$\sf : \implies \: \: 45 \times 2m$

So perimeter of field is 90m.

Now we have to find the cost of fencing.

Cost of fencing 1m=Rs.2.5

Cost of fencing 90m=90×Rs.2.5

=Rs.225

So cost of fencing is Rs.225

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NOTE- Kindly visit web to see diagram.

More formulae to know!

★Area of rectangle=length×breadth

★Area of square=Side²

★Perimeter of square=4×Side

★Area of circle=πr²

★Perimeter of circle=2πr

★Area of triangle=½×base×Height

★Perimeter of triangle=sum of all sides.