Looking for the speed of boat and current

Question

A boat makes a 336 mile roundtrip along a river. It takes 12 hours to get down stream and 14 hours to return. What is the speed of the boat in still water? What is the speed of the current?

I subbed for a math class & this was a worksheet question. The answers were provided, but I got a different answer for speed of boat (13 mph) than the key (26 mph).

What did I do wrong?

Answer 1

Let x = speed of boat in still water

     y = speed of current

 

Speed of boat upstream = x-y

Speed of boat downstream = x+y

 

Distance = (Rate)(Time)

 

12(x+y) = 168

14(x-y) = 168

 

Divide the first equation by 12 and the second by 14:

 

 x + y = 14

 x - y = 12

 

So, 2x = 26   x = 13 mph

                   y = 1 mph

 

It seems that the answer in the key is incorrect.