rahul is construction his house he wants to make a hall of dimensions 20 m *1 5m, such - Maths - Perimeter and Area

Question

rahul is construction his house he wants to make a hall of
dimensions 20 m *1 5m, such that it has a border of black granite 0
5 m wide on all four sides and a black granite circle in the middle
of radius 1 4 m calculate the cost of granite used at rs 1200 per
square metre

Ayush Jha · Accepted Answer

We have the following diagram

So dimension of the hall is (20m x 15 m) Thickness of granite surface is 0 5 m So Dimensions of rectangle PQRS is (19m x 14m) Radius of circle(r) = 1 4 m Area of the granite surface = Area of ABCD - Area of PQRS + Area of circle $= 15 \times 20 - 14 \times 19 + \frac{22}{7} {(1 4)}^{2} = 300 - 266 + \frac{308}{50} = 34 + 6 16 = 40 16 m^{2}$ The cost of granite used at Rs 1200 per square metre is $= 1200 \times 40 16 = R s 48192$

rahul is construction his house . he wants to make a hall of dimensions 20 m *1 5m, such that it has a border of black granite 0.5 m wide on all four sides and a black granite circle in the middle of radius 1.4 m . calculate the cost of granite used at rs 1200 per square metre.