Mr. R went kayaking in a river. Paddling at a constant rate against the current for 20 km from Town A to Town B took him 4 hours. The return trip with the curre

Question

Mr. R went kayaking in a river. Paddling at a constant rate against the current for 20 km from Town A to Town B took him 4 hours. The return trip with the current took 2.5 hours. Rate of current and paddler?

Answer 1

distance=rate*time

d=rt

20=(r-c)*4

20=(r+c)*2.5

divide both sides of equation 1 by 4 and divide both sides of equation 2 by 2.5

5=r-c

8=r+c

add the equations

13=2r

r=13/2

r=6.5 kph is the rate of the paddler

8=6.5+c

8-6.5=c

c=1.5 kph is the rate of the current