The Chen family and the Davis family each used their sprinkles last summer. The water output rate for the Chen Family's sprinkler was 25 L per hour. The water output for the Davis family's sprinkler was 15 L per hour. The families used their sprinklers for a combined total of 55 hours, resulting in a total water output of 1175 L. How long was each sprinkler used?

Answer 1

Let x be the number of hours the Chen family used their sprinkler.
The Chen family's sprinkler outputted 25x liters of water.
The Davis family sprinkler was then used for 55 - x hours.
The Davis family's sprinkler outputted 15(55-x) liters of water.
25x + 15(55-x) = 1175
25x + 825 - 15x = 1175
10x = 350
x = <<35=35>>35
The Chen family used their sprinkler for 35 hours.
The Davis family used their sprinkler for 55 - 35 = <<55-35=20>>20 hours. Answer: \boxed{20}.