SOLUTION: A boat travels 45 mi upstream(against the current) in 5 h.The boat travels the same distance downstream in 3 h.What is the rate of the boat in still water?What is the rate of the c

Algebra.Com
Question 28421: A boat travels 45 mi upstream(against the current) in 5 h.The boat travels the same distance downstream in 3 h.What is the rate of the boat in still water?What is the rate of the current?
Answer by Paul(988)   (Show Source): You can put this solution on YOUR website!
Let the speed of the boat be y
Let the speed of the current be x
5(x-y)=45 ---> solve for y
5x-5y=45
-5y=45-5x
y=9+x
Subsitution

3(x+y)=45
3x+3y=45 (allow subsitution)
3x+3(9+x)=45
3x+27+3x=45
6x=18
x=3

y=9+3
y=12

Hence, the speed of the current is 3mph and the speed of the boat is 12mph.
Paul.

RELATED QUESTIONS

A boat travels 45 mi upstream (against the current) in 5h. the boat travels the same... (answered by checkley71)
a boat travels 45 mi upstream (against the current) in 5h. The boat travels the same... (answered by lwsshak3)
A boat travels 45 mi upstream (against the current) in 5 hours The boat travels same... (answered by jorel1380)
A BOAT TRAVELS 60 KM UPSTREAM (AGAINST THE CURRENT) IN 5 HOURS. THE BOAT TRAVELS THE SAME (answered by sudhanshu_kmr)
A boat travels 60 km upstream (against the current) in 5 hours. the boat travels the... (answered by mananth)
A boat travels 60km upstream (against the current) in 5 hours. The boat travels the same... (answered by mananth)
A boat travels 60 km upstream, (against the current) in 5 hours. The boat travels the... (answered by checkley77)
A boat travels 60 km upstream, (against the current) in 5 hours. The boat travels the... (answered by checkley77)
A boat travels 60 km upstream (against the current) in 5 hours. The boat travels the same (answered by checkley77)