Question

The floor of a rectangular hall has a perimeter of 300 M. Its height is 10 m. There are two doors of 5 m x 3 m and four windows of 3 m x 1.5 m. Find the cost of painting of its four walls at the rate of Rs.30 per m².

Answer 1

Answer:

Cost of painting of its four walls :88,560 Rs

Step-by-step explanation:

Perimeter of Floor Rectangular hall = 300 m

$2(l + b) = 300 \: m$

Height of room= 10 m

Area of one door =

$l \times b \\ \\ = 5 \times 3 \\ \\ = 15 \: {m}^{2}$

Area of two doors = 2×15 = 30 sq-m

Area of four windows

$= 4 \times (l \times b) \\ \\ = 4 \times 3 \times 1.5 \\ \\ = 12 \times 1.5 \\ \\ = 18 \: {m}^{2}$

Area of four walls =

$= 2lh + 2bh \\ \\ = 2h(l + b) \\ \\ = 10 \times 300 \\ \\ = 3000 \: {m}^{2}$

Total area of walls to be painted= Area of walls- Area of 2 doors - Area of four windows

Total area of walls to be painted

$= 3000 - 30 - 18 \\ \\ = 2952 \: {m}^{2}$

cost of painting 30 Rs per m²

Cost of painting of its four walls :

$= 2952 \times 30 \\ \\ = 88560 \: Rs$

Hope it helps you.