+0  
 
0
1057
1
avatar

A boat traveled 144 miles downstream and back. The trip downstream took 4 hours. The trip back took 9 hours. Find the speed of the boat in still water and speed of the current.

 Feb 25, 2020
 #1
avatar+23245 
0

Let  b  =  rate of the boat.

Let  r  =  rate of the river.

 

The rate going downstream is  b + r.

The rate going upstream is  b - r.

 

rate x time  =  distance

 

4(b + r)  =  144     --->     b + r  =  36     [divide both sides by 4]

9(b - r)  =  144      --->     b - r  =  16      [divide both sides by 9]

Add town:                          2b  =  52  

Divide by :                           b  =  26  mi/hr

                                            r  =  10  mi/hr

 Feb 26, 2020

1 Online Users

avatar