Question

The length, breadth and height of a room are 5 m, 4 m and 3 m respectively. Find the cost of white washing the walls of the room and the ceiling at the rate of Rs 7.50 per m2.

Answer 1

Answer:

dimensions of room=5m×4m×3m

area for white washing=csa+ar(top)

=2(l+b)*h+ l*b

=2(5+4)3+5*4

=54+20

$74m^{2}$

cost of painting=74×7.50= 555rupees

Answer 2

Answer:

Given length breadth and height of a room is 5m,4mand 3m

Do A/Q we need to find the total cost required for the white washing the room at the rate of ₹7.50 per m²

So for this we first need to calculate out the Curved surface area of the room

So the formula to find CSA is

$\bold{ \red{CSA \: = 2 \times (length + breadth )\times height}}$

So let us calculate

$= > CSA = 2 \times (5 + 4) \times 3 \\ \\ = >CSA = \: 2 \times 9 \times 3 \\ \\ = > CSA \: = 54m ^{2}$

So A/Q

1m²=₹7.50

$\therefore54m ^{2} = 54 \times 7.50 \\ \\ = > \: \huge{\red {RS = \: 405}}$