Question

The butler family and Clark family each used their sprinklers last summer. The butler family's sprinklers was used for 40 hours. The Clark family's sprinkler was used for 30 hours. There was a combined total output of 2200L of water. What was the water output rate for each sprinkler if the sum of the two rates was 60l per hour?

Answer 1

Answer: the sprinkling rate of the butler family's sprinkler is 40L per hour

the sprinkling rate of the Clark family's sprinkler is 20L per hour

Explanation:

Let x represent the sprinkling rate of the butler family's sprinkler.

Let y represent the sprinkling rate of the Clark family's sprinkler.

The butler family's sprinklers was used for 40 hours. The Clark family's sprinkler was used for 30 hours. There was a combined total output of 2200L of water. This means that

40x + 30y = 2200 - - - - - - - - - - -1

if the sum of the two rates was 60l per hour, it means that

x + y = 60

Substituting x = 60 - y into equation 1, it becomes

40(60 - y) + 30y = 2200

2400 - 40y + 30y = 2200

- 40y + 30y = 2200 - 2400

- 10y = - 200

y = - 200/ - 10

y = 20

Substituting y = 20 into x = 60 - y, it becomes

x = 60 - 20 = 40