SOLUTION: The riverboat can travel 80 miles downstream in 5 hours but requires 8 hours to travel and 48 miles upstream. What is the speed of the riverboat in still water, and what is the sp

Question 625309: The riverboat can travel 80 miles downstream in 5 hours but requires 8 hours to travel and 48 miles upstream. What is the speed of the riverboat in still water, and what is the speed of the current?
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
The riverboat can travel 80 miles downstream in 5 hours but requires 8 hours to travel and 48 miles upstream. What is the speed of the riverboat in still water, and what is the speed of the current
**
lex=speed of boat in still water
let c=speed of current
x+c=speed of boat downstream
x-c=speed of boat upstream
travel time=distance/speed
..
80/(x+c)=5
48/(x-c)=8
..
5x+5c=80
8x-8c=48
..
40x+40c=640 (mult. by 8)
40x-40c=240 (mult. by 5)
add
80x=880
x=11
5c=80-5x=80-55=25
c=5
speed of boat in still water=11 mph
speed of current=5 mph

RELATED QUESTIONS
I dont even know where to start with this problem. The boat can travel 112 miles... (answered by dabanfield)

It takes 5 hours for a boat to travel 80 miles downstream. The boat can travel the same... (answered by ikleyn,greenestamps)

The boat could travel 112 miles downstream in 4 hours but required 6 hours to travel 48... (answered by checkley71)

a boat travels 2 miles upstream and 2 miles downstream in 5 hours. in still water, the... (answered by mananth)

A riverboat can travel downstream from port A to port B at 20 mph. It can travel upstream (answered by josmiceli)

A boat can travel 5 miles upstream and 5 miles downstream in a total of 6 hours. If the... (answered by ankor@dixie-net.com)

A boat can travel 5 miles upstream and 5 miles downstream in a total of 6 hours. If the... (answered by emargo19)

What is the speed of a boat and a current, if a boat travels 48 miles downstream in three (answered by Maths68)

The current of a river is 2 miles per hour. It takes a motorboat a total of 3 hours to... (answered by amoresroy)