The Sanders family and the Henderson family each used their sprinklers last summer. The water output rate for the Sanders family's sprinkler was 40 L per hour. The water output rate for the Henderson family's sprinkler was 30 L per hour. The familles used their sprinklers for a combined total of 70 hours, resulting
in a total water output of 2400 L. How long was each sprinkler used?
Note that the ALEKS graphing calculator can be used to make computations easier.