Question 1102790: A sea turtle is out for a swim. with the current, it can travel 35 miles in 5 hours . In the same time, it can travel 15 miles against the current. Find the speed of the sea turtle and the speed of the current.
So I tried doing this to solve it,
(x+y) speed with current
(x-y) speed against current
Using distance = time x speed
5(x+y)=35
5(x-y)=15
Found 3 solutions by josmiceli, ikleyn, richwmiller:
Answer by josmiceli(19441)   (Show Source):
Answer by ikleyn(52898)  (Show Source):
You can put this solution on YOUR website! .
You are on the RIGHT track.
Your next steps are THESE:
From your equations, you have
x + y =  ,
x - y =  ,
or, which is the same,
x + y = 7, (1)
x - y = 3. (2)
Now add the equations (1) and (2). You will get
2x = 7 + 3 = 10, which implies x =  = 5.
So, the turtle speed in still water is 5 miles per hour. (<<<---=== at this place I fixed "the slip of my pen").
( Thanks to @richwmiller for noticing it !)
Next, from the equation (1) you have
y = 7 - x = 7 - 5 = 2 miles per hour.
Answer. The turtle speed in still water is 5 miles per hour.
The speed of the current is 2 miles per hour.
Please make CHECK on your own. It is VERY USEFUL and EDUCATIONAL step in such problems. (And the necessary step, too !)
Answer by richwmiller(17219)  (Show Source):
You can put this solution on YOUR website! I believe tutor Ikleyn had a slip of the pen.
Her conclusion is correct but an intermediary step is incorrect.
She said "So, the speed of the current is 5 miles per hour."
but her final answer is
"Answer. The turtle speed in still water is 5 miles per hour.
The speed of the current is 2 miles per hour."
|
|
|
