The Henderson family and the Richardson family each used their sprinklers last summer. The water output rate for the Henderson family’s sprinklers was 25 L per hour. continued at the bottom

Question

The water output rate for the Richardson family’s sprinkler was 30 L per hour. The families used their sprinklers for a combined total of 45 hours, resulting in a total of 1250 L. How long was each sprinkler used?

Answer 1

25H + 30R = 1250

H+R = 45

multiply by 25

25H + 25R = 25(45) = 1125

subtract last equation from first equation

5R = 125

divide by 5

R = 25 hours for the Richardson family

H=45-25 = 20 hours for the Henderson family