Question

The internal measure of a cuboid room are $12m\times 8m\times 4m$ Find the total cost of white washing all four walls of a room. If the cost of white washing is $8per{m}^2$ what will be the cost of white washing of the celling of the room is also white washed.

• A. $Rs2028$
• B. $Rs4048$
• C. $Rs2048$
• D. $Rs1048$

Answer 1

Answer: (C)

$Rs2048$

Dimension of the romm$=12m\times 8m\times 4m$

Lateral surface area$=2(l+b)h$

$=2(12+8)4$

$=8\times 20$

$=160m^2$

Cost of white washing$=Rs8per{m}^2$

Cost of white washing of room$=160\times 8=Rs1280$

Area od ceiling$=12\times 8=96m^2$

So,

Cost of white washing of ceiling$=96\times 8=Rs768$

Therefore,

Total cost of white washing of room and ceiling$=1280+768=Rs2048$