Big Plane question?

2 ⤊

A six-passenger plane cruises at 180 mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind, then what is the wind speed?

2007-02-22 14:19:10 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics

2 answers

With no wind, the distance traveled would be 6 miles. Since the plane speed is 180 mph without wind, the plane flew for two minutes. One extra mile in two minutes means the wind speed is .5 mi/min or 30 mph.

2007-02-22 14:24:31 · answer #1 · answered by christopher_az 2 · 1⤊ 0⤋

(180 + w)/7 = (180 - w)/5
5w + 900 = 1260 - 7w
12w = 360
w = 30 mph

2007-02-23 00:31:21 · answer #2 · answered by Helmut 7 · 1⤊ 0⤋