Posted by Christian on .
Flying with wind, a plane flew 800 miles in 5 hrs. Flying against the wind, the plane flew the same distance in 8 hrs. Find the still air speed and wind speed.

Algebra 
Steve,
If the plane's air speed is s, and the wind speed is w
800/(s+w) = 5
s+w = 160
800/(sw) = 8
sw = 100
2s=260
s=130
so, w=30
800/160 = 5
800/100 = 8