Question
Simon and Henry take 4 days to assemble a toy house. Henry and Vincent take 4 days to build the same house while Simon and Vincent take only 5 days. How many complete days would the three of them take to build the same toy house?
4 m

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Simon and Henry take 4 days to assemble a toy house. Henry and Vincent take 4 days to build the same house while Simon and Vincent take only 5 days. How many complete days would the three of them take to build the same toy house?