Question

answer please..... ..................

Answer 1

20 hours will be taken by 4 men to build the wall

Answer 2

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I saw your questions now they are mostly Brain Teaser. If this question is also one of these then , your answer goes like this.

In the question it is given that 8 men built a wall in 10 hours then in how much time 4 men will build that wall.As wall is already built , so there is no need of making it again.
So, the answer is 0 hour.