Question

A room 8m by 9m has a border made up of semicircular black marbles.the radius of each marble is 0.5 metre.the remaining floor is covered with white marble.find the cost of marbling at the rate of rs.140 per sq. m for black marble and rs.105 per sq.m for white marble.​

Answer 1

Answer:

◆ Answer -

White marble = 23.2 sq.m

Green marble = 2 sq.m

● Explanation -

# Given -

L = 6 m

B = 4.2 m

t = 20 cm = 0.2 m

l = 6-0.2 = 5.8 m

b = 4.2-0.2 = 4 m

# Solution -

Area covered by white marble iz -

White marble = area of inner rectangle

White marble = l × b

White marble = 5.8 × 4

White marble = 23.2 sq.m

Area covered by green marble is -

Green marble = area of outer rectangle - area of innner rectangle

Green marble = L×B - l×b

Green marble = 6×4.2 - 5.8×4

Green marble = 2 sq.m