<PRE><B>Question 954196</B>
H=Howards; G=Grays
G+H=45
H=45-G
40H+25G=1500 Substitute for H
40(45-G)+25G=1500
1800-40G+25G=1500 Subtract 1800 from each side,
-15G=-300 Divide each side by -15
G=20 ANSWER 1: The Grays sprinkler was used 20 hours.
H=45-G=45-20=25 ANSWER 2: The Howards sprinkler was used 25 hours.
CHECK:
40H+25G=1500 
40(25)+25(29)=1500 
1000+500=1500
1500=1500







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