A man can row 50 km upstream and 72 km downstream in 9 hours.
A man can row 50 km upstream and 72 km downstream in 9 hours. He can also row 70 km upstream and 90 km downstream in 12 hours. Find the rate of current.
Answer/Solution
4 kmph
Steps/Work
Let x and y be the upstream and downstream speed respectively.
Hence, 50/x + 72/y = 9 and 70/x + 90/y = 12
Solving for x and y we get x = 10 km/hr and y = 18 km/hr
We know that Speed of the stream = 1/2 * (downstream speed - upstream speed) = 1/2 (18 - 10) = 4 km/hr.
ANSWER:D
Hence, 50/x + 72/y = 9 and 70/x + 90/y = 12
Solving for x and y we get x = 10 km/hr and y = 18 km/hr
We know that Speed of the stream = 1/2 * (downstream speed - upstream speed) = 1/2 (18 - 10) = 4 km/hr.
ANSWER:D