SOLUTION: A bird flew 12 miles in an hour aided by a tailwind. Then it turned and flew back against the wind but was unable to fly only 4 miles per hour. What was the speed of the wind? How

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Question 591501: A bird flew 12 miles in an hour aided by a tailwind. Then it turned and flew back against the wind but was unable to fly only 4 miles per hour. What was the speed of the wind? How fast would the bird have flown if there had been no wind?
Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A bird flew 12 miles in an hour aided by a tailwind. Then it turned and flew back against the wind but was unable to fly only 4 miles per hour. What was the speed of the wind? How fast would the bird have flown if there had been no wind?
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With-wind DATA:
distance = 12 miles ; time = 1 hr ; rate = d/t = 12/1 = 12 mph
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Against-wind DATA:
distance = 12 miles : rate = 4 mph
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Let "b" be speed of the bird in still air.
Let "w" be speed of the wind.
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Equation:
b + w = 12 mph
b - w = 4 mph
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Add and solve for "b":
2b = 16
b = 8 mph (speed of the bird in still air)
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Cheers,
stan H.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +s+ = the bird's speed with no wind
+s+%2B+w+ = bird's speed going with the wind
+s+-+w+ = bird's speed going against the wind
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going with the wind:
+12+=+%28+s+%2B+w+%29%2A1+
going against the wind:
+s+-+w+=+4+
+s+=+4+%2B+w+
By substitution:
+12+=+%28+4+%2B+w+%2B+w+%29%2A1+
+12+=+4+%2B+2w+
+2w+=+12+-+4+
+2w+=+8+
+w+=+4+
and
+s+=+4+%2B+w+
+s+=+4+%2B+4+
+s+=+8+
The speed of the wind is 4 mi/hr
The speed of the bird with no wind is 8 mi/hr