Question 385442
 The current in a stream is 2 mph. Find the speed of the boat in still water if it goes 26 miles downstream in the same amount of time it takes to go 18 miles upstream.
--------------------
Let speed of the boat be "b":
----
Downstream DATA:
distance = 26 miles ; rate = b+2 mph ; time = 26/(b+2) hrs.
-----------------------------------
Upstream DATA: 
distance = 18 miles ; rate = b-2 mph; time = 18/(b-2) hrs
=============
Equation:
time = time
26/(b+2) = 18/(b-2)
26(b-2) = 18(b+2)
---
26b-52 = 18b + 36
8b = 88 
b = 11 mph (speed of the boat in still water)
==========================
Cheers,
Stan H.