Six construction workers that work at the same rate can build a house in 1.5 days. How long does it take 15 construction workers, working at the same rate, to finish building a house? Express your answer as a fraction in lowest terms.
This is an inverse ratio. workers: time = 6:1.5 = 3:3.0 = 1:9.0. 15: (9.0/15 =0.6)
0.6 days = 6/10 = 3/5
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