10 people : 46 mins : 3 walls
x2 x2
20 people : 46 mins : 6 walls
÷5 x5
4 people : 230mins : 6 walls.
So it takes 230 mins for 4 people to paint 6 walls.
230 mins = 3 hours and 50 mins
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Answer: It takes 3 h 50 min for 4 people to paint 6 walls.
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