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| Question 151245:  I am using an online study guide for the COMPASS Assessment Test, I am having trouble with this particuluar word problem.  The problem involves d= rt.
 If 2 planes leave the same airport at 1:00 PM, how many miles apart will they be at 3:00 PM, if one travels directly north at 150 mph and the other plane travels directly west at 200 mph.
 A. 50 miles
 B. 100 miles
 C. 500 miles-correct answer
 D. 700 miles
 E. 1000 miles
 I originally answered the question D 700 miles, by taking 150+ 200, multiplying the answer by 2 for 2 hours.
 Found 2 solutions by  stanbon, scott8148:
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! If 2 planes leave the same airport at 1:00 PM, how many miles apart will they be at 3:00 PM, if one travels directly north at 150 mph and the other plane travels directly west at 200 mph. -------------------------
 North traveler goes 2*150 = 300 miles
 West traveler goes 2*200 = 400 miles
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 Use Pytagoras to find the distance of one plane to the other.
 d = sqrt[300^2 + 400^2] = sqrt[250000] = 500 miles
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 Cheers,
 Stan H.
 ============================
 
 A. 50 miles
 B. 100 miles
 C. 500 miles-correct answer
 D. 700 miles
 E. 1000 miles
 
Answer by scott8148(6628)
      (Show Source): 
You can put this solution on YOUR website! the two planes are flying at a right angle to each other (north and west) 
 their distances from the airport are the legs of a right triangle, and the distance from each other is the hypotenuse
 
 north bound __ d=rt __ d=150*2 __ d=300
 
 west bound __ d=rt __ d=200*2 __ d=400
 
 so the distance between them (hypotenuse) is ... think 3-4-5 __ or a^2+b^2=c^2
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