Question 954196
The Howard family and the Gray family each used their sprinklers last summer. The water output rate for the Howard family's sprinkler was 
40L per hour. The water output rate for the Gray family's sprinkler was 
25L per hour. The families used their sprinklers for a combined total of 
45 hours, resulting in a total water output of 
1500L. How long was each sprinkler used?
Howards family sprinklers: 25 hrs
Grays family sprinkler: 20 hrs
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let x=time Howards family sprinklers were used
45-x=time Grays family sprinkler were use
..
rate*time used=output
40x+25(45-x)=1500
40x+1125-25x=1500
15x=375
x=25
45-x=20