Question

a room is three times as long as its broad and it height is 4.6 M is the cost of carpeting its floor at rupees 60 per square metre is rupees 4500 find the cost of colouring the walls at rupees 18 per sq metre
ans is 1656​

Answer 1

Answer:

Dimensions of the room = (l metre * b metre * 4.6 metre)

Area of the floor = (l * b) sq metres

Now, l = 3b

So, area of the floor = 3(b^2) sq metres

Given, 3(b^2) * 60 = 4500

Or, (b^2) = 25

Or, b = ± 5, but b can't have a negative value

So, b = 5 and l = 15

Lateral surface area (area of four walls) of the room = {2 * (l + b) * 4.6} sq metres = (2 * 20 * 4.6) sq metres = 184 sq metres

Cost of colouring = (184 * 18) rupees = 3312 rupees

Answer 2

Dimensions of the room = (l metre * b metre * 4.6 metre)

area of the floor = (l * b) sq metres

now, l = 3b

so, area of the floor = 3(b^2) sq metres

given, 3(b^2) * 60 = 4500

or, (b^2) = 25

or, b = ± 5, but b can't have a negative value

so, b = 5 and l = 15

lateral surface area (area of four walls) of the room = {2 * (l + b) * 4.6} sq metres = (2 * 20 * 4.6) sq metres = 184 sq metres

cost of colouring = (184 * 18) rupees = 3312 rupees.