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put this solution on YOUR website!An executive flew in a corporate jet to a meeting in a city 1500 kilometers away.
After traveling the same amount of time on the return flight, the pilot mentioned that they still had 300 kilometers to go.
The air speed of the plane was 600 kilometers per hour.
How fast was the wind blowing? (Assume the wind direction was parallel to the flight path and constant all day.)
:
from the information given, we know the plane flew 1200 mi against the wind and 1500 mi with the wind in the same time interval.
:
Let w = speed of the window
then
(600+w) = effective speed to the city (tail wind)
and
(600-w) = effective return speed (against the wind)
:
Write a time equation; time = dist/speed
=
:
cross multiply
1200(600+w) = 1500(600-w)
:
simplify, divide by 100
12(600+w) = 15(600-w)
:
7200 + 12w = 9000 - 15w
12w + 15w = 9000 - 7200
27w = 1800
w =
w = 66
mph is the wind
:
:
Check this using 66.67 as the wind speed
1500/666.67 ~ 2.25 hrs
1200/533.33 ~ 2.25 hrs; confirms our solution
