Nancy and Diego are building model airplanes. Nancy has already built 5 model airplanes and Diego has built 0 model airplanes. Nancy can build 1 model airplane in an hour. Diego can build 2 model airplanes in an hour. How many hours will it take for Nancy and Diego to have an equal number of airplanes built if they both work non-stop?

Question

Answer:

5 hours

because Diego builds 2 per hour so 5 x 2 = 10 and navy does 1 per hour but has already built 5 so she also builds 10