Question

The perimeter of the floor of a room is 40 metreand it's height is 3.5metre find the area of four walls of the room also find the cost of papering the four walls at 35 rupees per metre square

Answer 1

perimeter = 2(l+b)
40 = 2(l+b)
l+b = 20 m

area of 4 walls = C.S.A. = 2h(l+b)

h = 3.5 m

csa= 2 × 3.5 (20)
= 7× 20
=140 sq.m.

rate of papering = Rs35/sq.m.

cost of papering = 35 × 140
= Rs 4900