A painter needed three days tp paint the walls of a room. How long would it take him, working at the same rate, to paint a room twice as long, twice as wide, and twice as high?

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7 thoughts to “A painter needed three days to paint the walls of a room”

U have a little bit misconception………………………..consider only walls & not the top & bottom.

surface area of wall=2ab+2bc+2ca.since everything is doubled now new surface area=2*2a*2b+2*2b*2c+2*2c*2a.i.e 4 times of tne existing one.hence days required=4*3= 12 days

U have a little bit misconception………………………..consider only walls & not the top & bottom.

Walls are 2 dimensional figure aren’t they. But he’s given 3 dimensions viz. Long, wide, high. How can it be? Can someone help me out?

surface area of wall=2ab+2bc+2ca.since everything is doubled now new surface area=2*2a*2b+2*2b*2c+2*2c*2a.i.e 4 times of tne existing one.hence days required=4*3= 12 days

Vittal….sorry friend your are wrong.Right answer has been given by Mohit and he also explained it.Better luck next time.

48 days

Hey Mohit…congratulations….you got it right.

Room 1 Surface area: 2 (LXH + WXH)

Room 2 Surface area: 2 (2LX2H +2WX2H)

Answer is 3 X 4 = 12 days