How much time does it take each person to make the round trip

Two piers, A and B, are located on a river. B is 1500 m downstream from A. Two friends must make round trips from pier A to pier B and return. One rows a boat at a constant speed of 4.50 km/h relative to the water. The other walks on the shore at a constant speed of 4.50 km/h. The velocity of the river is 2.40 km/h in the direction from A to B.
How much time does it take each person to make the round trip?

40.2 Min Person Walking
55.9 Min Person Driving
1500m= 1.5km
A. (1.5 +1.5)/4.50 For A Round Trip
t=0.67
t*60=40.2

B. 4.5+2.4=6.9 km/h From E-->W
1.5/6.9=.21739
4.5+(-2.40)=2.1 From W---> E
1.5/2.1=.7142857
.7142857+.21739=.9316
.9316*60=55.9


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