A lawn is in the form of a rectangle whose sides are in the ratio 5 : 3. The area of the lawn is 3375 m2. Find the cost of fencing the lawn at RS. 65 per metre.
Given: Cost of fencing lawn = Rs 65 per metre.
Area of lawn = 3375 m2
Length: Breadth = 5: 3
Let,
Length = 5x
Breadth = 3x
We know that,
Area of lawn = Length × Breadth
⇒ 3375 m2 = 5x × 3x
⇒ 3375 m2 = 15x2
⇒ x2 = 225 m2
⇒ x = 15 m
Therefore,
Length = 5x = 5 × 15 = 75 m
Breadth = 3x = 3 × 15 = 45 m
Now,
Perimeter of lawn = 2(length + breadth)
= 2(75 m + 45 m)
= 2 × 120 m
= 240 m
Hence,
Cost of Fencing = 240 m × Rs 65 per meter
= Rs 15600