<PRE><B>Question 951939</B>
T=Thomas usage; C=Clark usage
T+C=40hrs
T=40hrs-C
35L/hrT+15L/hrC=1100L Substitute for T
35L/hr(40hrs-C)+15L/hrC=1100L
1400L-35L/hrC+15L/hrC=1100L Subtract 1400L from each side.
-20L/hrC=-300L Divide each side by -20L/hr
C=15 hrs ANSWER 1: The Clarks used their sprinkler 15 hours.
T=40hrs-C=40hrs-15hrs=25 hrs The Thomases used their sprinkler 25 hours.
CHECK:
35L/hr(25 hrs)+15L/hr(15)=1100L
875L+225L=1100L
1100L=1100L


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