Question

the cost of plastering a wall of a room having length 8m and heights 4m at Rs 15 per m² is Rs 1560 . find the cost of carpeting the room at rs 300 per m²​

Answer 1

Explanation:

here ,

length = 8m

height=4m

Rate of plastering 4 walls = 15/m^2

Cost of plastering 4 wall = Rs 1560

Area of floor = Cost of plastering / Rate of plastering

= 1560/15

= 104

again,

Area of four wall = 2h(l+b)

or, 104= 2×4(8+b)

or, 104 =8(8+b)

or, 104/8=8+ b

or,13 - 8= b

or, b= 5

again,

Area of floor= l×b

= 8×5

= 40

again,

Rate of carpeting the floor= 300/ m^2

Area of floor = 40 m^2

cost of carpeting=Rate × Area

= 300×40

= 12000