<PRE><B>Question 1192951</B>
A kayak can travel 48 miles downstream in 4 ​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.
 Let k represent the speed of the kayak in still​ water, and let c represent the speed of the current. 

Write a distance equation for each way, dist = time * speed
4k + 4c = 48
and
24k - 24c = 48
simplify, divide by6
4k - 4k = 8
:
Add these two equation
4k + 4c = 48
4k - 4c = 8
----------------addition eliminates c, find k
8k + 0 = 56
k = 56/8
k = 7 mph is speed  of the kayak in still water
then using the first equation and k=7
4(7) + 4c = 48
28 + 4c = 48
4c = 48 - 28
4c = 20
c = 20/4
c = 5 mph is the rate of the current
:
:
Check this in the original 2nd equation
24(7) - 24(5) = 
168 - 120 = 48
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