SOLUTION: An airplane can travel 425 mph in still air. If it travels 4131 miles with the wind in the same length of time it travels 3519 miles against the wind, what is the speed of the wind

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Question 599626: An airplane can travel 425 mph in still air. If it travels 4131 miles with the wind in the same length of time it travels 3519 miles against the wind, what is the speed of the wind?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +w+ = the wind speed in mi/hr
Let +s+ = the speed in mi/hr of the plane in still air
Let +t+ = time of flights in hrs both with and against the wind
-----------
Flying with the wind:
+4131+=+%28+s+%2B+w+%29%2At+
(1) +4131+=+%28+425+%2B+w+%29%2At+
Flying against the wind:
+3519+=+%28+s+-+w+%29%2At+
(2) +3519+=+%28+425+-+w+%29%2At+
----------------------
(1) +t+=+4131+%2F+%28+425+%2B+w+%29+
(2) +t+=+3519+%2F+%28+425+-+w+%29+
+4131+%2F+%28425+%2B+w+%29+=+3519+%2F+%28+425+-+w+%29+
Multiply both sides by +%28+425+%2B+w++%29%2A%28+425+-+w+%29+
+4131%2A%28+425+-+w+%29+=+3519%2A%28+425+%2B+w+%29+
+1755675+-+4131w+=+1495575+%2B+3519w+
+7650w+=+1755675+-+1495575+
+7650w+=+260100+
+w+=+34+
The wind speed is 34 mi/hr
check:
(1) +4131+=+%28+425+%2B+34+%29%2At+
(1) +4131+=+459t+
{1) +t+=+9+ hrs
and
(2) +3519+=+%28+425+-+34+%29%2At+
(2) +3519+=+391t+
(2) +t+=+9+ hrs
OK