Question

The Patterson family and the bell family each used their sprinklers last summer. The wayer output rate for the patterson family's sprinkler was 25 L per hour. The water output rate for the bell family's speinkler was 15 L per hour. The familiez used their sprinklers for a combined total of 65 hours, resulting in a total water output of 1225 L. How long was each sprinkler used?

Answer 1

time of Bell's sprinklers --- x hrs
time of Patterson's ------- 65-x hrs

solve for x:

15x + 25(65-x) = 1225