NEEDING HELP WITH MATH

Question

The Morris family and the Watson family each used their sprinklers last summer. The Morris family's sprinkler was used for 30

 hours. The Watson family's sprinkler was used for 15

 hours. There was a combined total output of 1725L

 of water. What was the water output rate for each sprinkler if the sum of the two rates was 75L

 per hour?

Answer 1

1725/3= 575 L for watsons in 15 hours = 575/15 =115/3= 38 1/3 L per hour

1150 L for morrises in 30 hours = 1150/30 =115/3 = 38 1/3 L per hour

sum= 76 2/3 L per hour, if they sprinkle at the same rate

= about 75 L per hour combined

that's close, but you want closer, so

1725 is the total for 45 hours combine

it's like the distance formula d=rt

1725 = 30r + 15(75-r) = 30r + 1125 -15r

15r = 1725-1125 = 600

r = 600/15 = 40 L per hour for Morrises

75-40 = 35 L per hour for Watsons