Answer Of Simple Logical Mathematical Problem

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Did you answer 100?

"There are 5 people who can build 5 houses in just 5 days."

The above statement suggests that 1 man takes 5 days to build 1 house & not 1 man take 1 day to construct 1 house.

So 100 people will make 100 houses in only 5 days as each one completing the task in 5 days!