Lizzy: 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?.
Me: Hmmm, let me think. I think this is the detailed solution:
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Let F = the number of years Felipe needed to build his house. Emilio = 2F. 3F = 7.5 years. F = 2.5 years. 2.5 years = 30 months. It took Felipe 30 months to build his house. Final answer: 30.
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