Aquaman swims into a storm drain, from which water is flowing at an unknown rate. He swims 200 meters against the flow in 3 minutes. The he returns 150 meters with the flow in 0.7 minutes, before emerging through a manhole in the top of the drain.

Question

Harper Robertson

Mathematics

22 July, 22:49

Aquaman swims into a storm drain, from which water is flowing at an unknown rate. He swims 200 meters against the flow in 3 minutes. The he returns 150 meters with the flow in 0.7 minutes, before emerging through a manhole in the top of the drain.

+2

Answers (1)

Know the Answer?

Zhang · Answer 1

Answer: Aquaman swims at the rate of 140.47m/min

The rate of water drain is 73.81m/min

Step-by-step explanation: Let A be the rate at which Aquaman swims.

Let W be the rate at which the water drains

3 (A - W) = 200 ... equation (1)

0.7 (A + W) = 150 ... equation (2)

3A - 3W = 200 ... equation 3

0.7A + 0.7W = 150 ... eq4

Multiply eq 3 by 7 and eq 4 by - 30

21A - 21W = 1400

-21A + 21W = - 4500

Subtracting both equation from each other, you get

-42W = - 3100

W = 3100/42

W = 73.81m/min

Put 73.81 for W in equation 1

3A - 3 (73.81) = 200

3A - 221.43 = 200

A = 421.43/3

A = 140.47m/min