<human>:  Together Felipe and Emilio needed a combined time of 7.5 years to build their homes. Felipe finished in half the time of Emilio. How many months did it take Felipe to build his house?
<bot>: Define a variable ** Let F = the number of years Felipe needed to build his house
How many years did Emilio need to build his house? ** Emilio = <<2=2>>2F
Write an equation ** 3F = 7.5 years
Divide by 3 ** F = <<2.5=2.5>>2.5 years
How many months did Felipe need to build his house? ** 2.5 years = 30 months
How many months did it take Felipe to build his house? ** It took Felipe 30 months to build his house.
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