Question 229129
Ben is a piolet for Air Airwas. He computes his flight time against a headwind for a trip of 2900 mi at 5 hr. The flight would take 4 hr and 50 min if the headwind were half as great. Find the headwind and the planes air speed.
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Use d = rt
r = airspeed, w = wind speed
2900 = (r-w)*300 (time in minutes)
2900 = (r - w/2)*290
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29 = 3r - 3w
290 = 29r - 29w/2 --> 580 = 58r - 29w
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3r - 3w = 29 Eqn 1
58r-29w = 580 Eqn 2
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87r - 87w = 841 Eqn 1 x 29
174r- 87w = 1740 Eqn 2 x 3
------------------ Subtract
-87r = -899
r = 31/3 miles/minute
r = 620 mph ( = airspeed)
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29 = 3r - 3w
3w = 3r - 29 = 31 - 29
w = 2/3 miles/minute
w = 40 mph (headwind speed)