A path 5m wide is to be built along the border and inside a square garden of side 90m. Find the cost of cementing the path at the rate of Rs.10 per meter square.

Total cost of cementing the path = Rs. 17,000.

Step-by-step explanation:

Let the square garden be ABCD

Let the region inside the garden (ABCD) be WXYZ.

Given the following data;

Length of sides of ABCD = 90m

Width of path = 5m

Cost = Rs. 10 per m²

Area of ABCD = 90 * 90

Area of ABCD = 8100m²

To find the area of WXYZ;

WX = WZ = 90 - (5 + 5)

WX = WZ = 90 - 10

WX = WZ = 80m

Area of WXYZ = WX * WZ

Substituting into the equation, we have;

Area of WXYZ = 80 * 80

Area of WXYZ = 6400 m²

Area of path = Area of ABCD - Area of WXYZ

Area of path = 8100 - 6400

Area of path = 1700 m²

Total cost of cementing the path = Area of path * cost

Total cost of cementing the path = 1700 * 10

Total cost of cementing the path = Rs. 17,000