A man can row three quarters of a km against the stream in 11 1/2 minutes and return in 7 1/3 minutes.Find the speed of the man in still water.What is the speed of the streamSelect one:a. None of theseb. 6 km/hr,2 km/hrc. 5·025 km/hr,1·115 km/hrd. 4 km/hr,1 km/hr

To solve this problem, we need to find the speed of the man in still water and the speed of the stream.

Step 1: Convert the time to hours The man rows 3/4 km against the stream in 11 1/2 minutes, which is 11.5/60 = 0.192 hours. He returns in 7 1/3 minutes, which is 7.33/60 = 0.122 hours.

Step 2: Calculate the speed against and with the stream Speed = Distance/Time Against the stream: Speed = 0.75 km / 0.192 hours = 3.91 km/hr With the stream: Speed = 0.75 km / 0.122 hours = 6.15 km/hr

Step 3: Calculate the speed of the man in still water and the speed of the stream Let's denote the speed of the man in still water as x and the speed of the stream as y. We know that when the man rows against the stream, his effective speed is (x-y), and when he rows with the stream, his effective speed is (x+y).

So we have the system of equations: x - y = 3.91 x + y = 6.15

Solving this system, we get: x = (3.91 + 6.15) / 2 = 5.03 km/hr y = (6.15 - 3.91) / 2 = 1.12 km/hr

So, the speed of the man in still water is approximately 5.03 km/hr and the speed of the stream is approximately 1.12 km/hr.

The closest answer to these values is option c. 5·025 km/hr,1·115 km/hr.