SOLUTION: 1. A search plane has a cruising speed of 250 miles per hour and carries enough fuel for at most 5 hours of flying. If there is a wind that averages 30 miles per hour and the direc

Algebra ->  Customizable Word Problem Solvers  -> Misc -> SOLUTION: 1. A search plane has a cruising speed of 250 miles per hour and carries enough fuel for at most 5 hours of flying. If there is a wind that averages 30 miles per hour and the direc      Log On

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Question 1207788: 1. A search plane has a cruising speed of 250 miles per hour and carries enough fuel for at most 5 hours of flying. If there is a wind that averages 30 miles per hour and the direction of the search is with the wind one way and against it the other, how far can the search plane travel before it has to turn back?

2. Rescue at Sea A life raft, set adrift from a sinking ship 150 miles offshore, travels directly toward a Coast Guard station at the rate of 5 miles per hour. At the time that the raft is set adrift, a rescue helicopter is dispatched from the Coast Guard station. If the helicopter’s average speed is 90 miles per hour, how long will it take the helicopter to reach the life raft?

Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.
1. A search plane has a cruising speed of 250 miles per hour and carries enough fuel
for at most 5 hours of flying. If there is a wind that averages 30 miles per hour and
the direction of the search is with the wind one way and against it the other,
how far can the search plane travel before it has to turn back?
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Let d be one-way distance, in miles.


Time to fly with    the wind is  d%2F%28250%2B30%29 = d%2F280  hours.

Time to fly against the wind is  d%2F%28250-30%29 = d%2F220  hours.


Total time flying in both directions is  d%2F280 + d%2F220  hours.


An equation for the maximum possible distance d is

    d%2F280 + d%2F220 = 5  hours.


To solve, multiply both sides by 280*220.  You will get

    220d + 280d = 5*280*220


Simplify and find d

        500d   = 308000

           5d  =  3080

             d = 3080/5 = 616.


ANSWER.  The maximum one way distance is at most 616 miles.


CHECK.   616%2F280 + 616%2F220 = 2.2 + 2.8 = 5 hours.

Solved.


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By the way, I found that this problem was solved at this forum several/many years ago. See the links

https://www.algebra.com/algebra/homework/word/travel/Travel_Word_Problems.faq.question.200086.html#google_vignette

https://www.algebra.com/algebra/homework/word/travel/Travel_Word_Problems.faq.question.646572.html#google_vignette


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Comment from student: Perfect. How about question 2? Rescue at Sea A life raft, set adrift from a sinking ship
150 miles offshore, travels directly toward a Coast Guard station at the rate of 5 miles per hour.
At the time that the raft is set adrift, a rescue helicopter is dispatched from the Coast Guard station.
If the helicopter’s average speed is 90 miles per hour, how long will it take the helicopter to reach the life raft?
Here is my set up: 5x + 90x = 150 Correct?


My response : Yes, it is correct.
You may continue from this point.


At this forum, there is a rule and a policy: One and only one problem per post.

Therefore, please do not pack more than one problem per post.