SOLUTION: The current in a stream moves at a speed of 8 km/h. A boat travels 15 km upstream and 15 km downstream in a total time of 2 hr. What is the speed of the boat in still​ water
Algebra.Com
Question 1057406: The current in a stream moves at a speed of 8 km/h. A boat travels 15 km upstream and 15 km downstream in a total time of 2 hr. What is the speed of the boat in still water?
Found 2 solutions by jorel555, ikleyn:
Answer by jorel555(1290) (Show Source): You can put this solution on YOUR website!
Let s be the speed of the boat in still water. Then:
15/(s+8) + 15/(s-8)=2
15(s-8)+15(s+8)=2(sē-64)
2sē-30s-128=0
sē-15s-64=0
Using the quadratic formula, , we get two roots of 18.4658560997 and -3.46585609973. Throwing out the negative result, we get the speed of the boat in still water to be 18.47 kph. ☺☺☺☺
Answer by ikleyn(52776) (Show Source): You can put this solution on YOUR website!
.
For detailed solutions of Upstream-Downstream Travel and Distance problems see the lessons
- Wind and Current problems
- More problems on upstream and downstream round trips
- Selected problems from the archive on the boat floating Upstream and Downstream
Read them attentively and learn how to solve this type of problems once and for all.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this textbook under the section "Word problems", the topic "Travel and Distance problems".
RELATED QUESTIONS
The current in a stream moves at a speed of 5 km/h. A boat travels 39 km upstream and 39... (answered by Alan3354)
The current in a stream moves at a speed of 3km/h. A boat travels 40 km upstream and 40... (answered by josmiceli)
The current in a stream moves at a speed of 4mi/h. A boat travels 4 miles upstream and 28 (answered by jorel1380)
The current of a stream moves at a speed of 5km/hr. The boat travels 31 km upstream and... (answered by stanbon)
The current in a stream moves at a speed of 4 km/ h. A boat travels 17 km upstream and 17 (answered by jorel555)
The speed of a boat in still water is 15 km/h. The boat travels 40 km upstream and 40 km... (answered by scott8148)
A boat moves 28 km/h in still water. It travels 80 km upstream and 80 km downstream in a... (answered by mananth)
The speed of a boat in still water is 8 km/h. It travels 60 km upstream and 60 km... (answered by mananth,ankor@dixie-net.com,Alan3354)
The speed of a boat in still water is 10 km/h. The boat travels 12 km upstream and 28 km... (answered by jorel1380)