A kayak can travel 48 miles downstream in 8 hours, while it would take 24 hours to make the same trip upstream. Find the speed of the kayak in still​ water, as well as the speed of the current?

1 Answer
Mar 5, 2018

Still water kayak speed is 4miles/hr
Speed of current is 2miles/hr.

Explanation:

Assume speed of te kayak in still wate= k miles/hr
Assume speed of river current = c miles/hr

When going dwon stream : 48 miles in 8 hrs =6 miles/hr
When goinf up stream : 48 miles in 24hrs = 2miles/hr

When kayak is travelling downstream, the current helps the kayak,

#k + c=6#

In reverse direction, kayak going against stream:

#k -c= 2#

Add above two equatios:
#2k =8#

so #k=4#

Substitute value for k in first equation:

#4 +c =6#

So #c=6-4# = #2#

Still water kayak speed is 4miles/hr

Speed of current is 2miles/hr.