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?
Let F = the number of years Felipe needed to build his house
Emilio = <<2=2>>2F
3F = 7.5 years
F = <<2.5=2.5>>2.5 years
2.5 years = 30 months
It took Felipe 30 months to build his house.
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