SOLUTION: The Kim family and the Chen family each used their sprinklers last summer. The water output rate for the Kim family's sprinkler was 40L per hour. The water output rate for the Chen

Algebra ->  Equations -> SOLUTION: The Kim family and the Chen family each used their sprinklers last summer. The water output rate for the Kim family's sprinkler was 40L per hour. The water output rate for the Chen      Log On


   

Question 739862: The Kim family and the Chen family each used their sprinklers last summer. The water output rate for the Kim family's sprinkler was 40L per hour. The water output rate for the Chen family's sprinkler was 20L per hour. The families used their sprinklers for a combined total of 35 hours, resulting in a total water output of 1100L . How long was each sprinkler used?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +h+ = hours of use by Kim family
+35+-+h+ = hours of use by Chen family
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+40h+%2B+20%2A%28+35+-+h+%29+=+1100+
+40h+%2B+700+-+20h+=+1100+
+20h+=+400+
+h+=+20+
+35+-+h+=+15+
20 hours of use by Kim family
15 hours of use by Chen family