directly west

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directly west

by sanju09 » Thu Mar 19, 2009 5:40 am
If two 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 travels directly west at 200 mph?
A. 50 miles
B. 100 miles
C. 500 miles
D. 700 miles
E. 1,000 miles



OA C
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by DanaJ » Thu Mar 19, 2009 5:52 am
Directly north and directly west make the cathti of a right triangle, so the distance you are looking for is the hypotenuse of this triangle.

The one that that travels north travels 2 hours, speed 150 mph. This means the distance from the airport will be 2*150 = 300 miles.

The one that travels west has an average speed of 200 mph, meaning its distance from the airport will be 2*200 = 400 miles.

Distance between the two: sqrt(400^2 + 300^2) = 500 miles.
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by Scott@TargetTestPrep » Tue Aug 06, 2019 4:46 pm
sanju09 wrote:If two 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 travels directly west at 200 mph?
A. 50 miles
B. 100 miles
C. 500 miles
D. 700 miles
E. 1,000 miles



OA C
The paths of the planes create right triangle, with the distance between them equaling the hypotenuse of the triangle.

The distance of the first plane from the airport at 3:00 PM (2 hours after departure) is 2 x 150 = 300.

The distance of the second plane from the airport at 3:00 PM (2 hours after departure) is 2 x 200 = 400.

Thus, the distance between the two planes is 500, since we have a 300-400-500 right triangle.

Answer: C

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