Question

The dimensions of a room are 21m x 12m x 4m. Find the cost ofwhitewashing all the four walls and ceiling at the rate of Rs 8 per m².​

Answer 1

Step-by-step explanation:

Area of four walls =2(l+b)×h

so,Area of four walls =2(21+12)×4m

Area of ceiling=(l×b)

so.area of ceiling =(21×12)m

then add them

total area =area of four walls +area of ceiling

now,

multiply it by rs.8

cost=8×total area