Q. 54.3( 213 Votes )
Daniel is painting the walls and ceiling of a cuboidal hall with length, breadth and height of 15 m, 10 m and 7 m respectively. From each can of paint 100 m2 of area is painted. How many cans of paint will she need to paint the room?
Answer :
Let length, breadth and height of room be l, b and h respectively
Given,
l = 15 m
b = 10 m
h = 7 m
and we know, area of four walls = 2(l + b)h
Hence,
Area to be painted = Area of four Walls of a Room + area of ceiling
= 2(l + b)h + lb
= 2(15 + 10)7 + 15(10)
= 14(25) + 150
= 350 + 150
= 500 m2
As, one can of paint is enough for 100 sq m
So, 500/100 = 5 cans are needed to paint the hall.
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