SOLUTION: A boat can travel 24 miles downstream in 2 hrs. The return trip takes 3 hrs. Find the speed of the boat in still water.
Algebra.Com
Question 1131032: A boat can travel 24 miles downstream in 2 hrs. The return trip takes 3 hrs. Find the speed of the boat in still water.
Found 4 solutions by Alan3354, stanbon, josgarithmetic, greenestamps:
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Been done at least 100's of times.
Look it up.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A boat can travel 24 miles downstream in 2 hrs. The return trip takes 3 hrs. Find the speed of the boat in still water.
-------
Downstream rate = 24 miles/2 hrs = 12 mph
Upstream rate = 24 miles/3 hrs = 8 mph
-------------------------
Let" "b" be the speed of the boat in still water; Let "c" be the current rate.
-----
Equations:
b + c = 12 mph
b - c = 8 mph
----------
2b = 20 mph
b = 10 mph (boat speed in still water)
--------------------
Cheers,
Stan H.
----------
Answer by josgarithmetic(39616) (Show Source): You can put this solution on YOUR website!
r, boat speed without current
c, speed of current
If boat goes downstream L miles in x hours and makes return trip upstream in y hours, then system of equations for this is:
You can use Elimination Method to solve for r and c.
Answer by greenestamps(13198) (Show Source): You can put this solution on YOUR website!
Use the given information about distances and times to find that the upstream speed is 8mph and the downstream speed is 12mph. Then use the following common sense reasoning to find the speed of the boat and the speed of the current.
12mph is the speed you get when you take the boat's speed and ADD the speed of the current; 8mph is the speed you get when you take the boat's speed and SUBTRACT the speed of the current.
A bit of logical reasoning then tells you the speed of the boat has to be halfway between 12mph and 8mph.
So the boat's speed is 10mph and the speed of the current is 12-10 = 2mph.
Here is an example of another common type of problem that can be solved quickly using the same logical reasoning, without the need for formal algebra.
The sum of two numbers is 30; their difference is 6. Find the two numbers.
Exactly as with your problem involving the speed of the boat and the speed of the current, in this problem one of the numbers has to be halfway between 6 and 30, which is 18; then the other number is the difference between 18 and either 6 or 30, which is 12.
RELATED QUESTIONS
A sightseeing boat travels 3 hrs. on a trip downstream with a 2.5mph current. The return... (answered by ankor@dixie-net.com)
A motorboat takes 3 hrs to travel 144 km going upstream the return trip... (answered by josmiceli,Alan3354)
A boat can travel 24 miles downstream in 2 hours and can make the return trip in 3 hours. (answered by ewatrrr)
Find the speed of a motor boat in still water and the speed of a river current, if it... (answered by Paul)
a boat travels 24 mi uptream in 3 hrs. it hen takes 3 hrs to go 36 mi downstream. find... (answered by checkley77)
Use two equations in two variables to solve the application.
A boat can travel 24... (answered by ikleyn)
A riverboat can travel 30km downstream in 3 hrs & can make the return trip in 5 hrs. Find (answered by josgarithmetic)
A boat can go 72 miles downstream in 3 hours, and can make the return trip in 4 hours.... (answered by tommyt3rd)
A motor boat takes 5 hrs to travel 300 mi going upstream. The return trip takes 2hrs.... (answered by mananth)