Question 213770
D=RT
20=R*.4
20=.4R
R=20/.4
R=50 MPH. WITH THE WIND.
20R=R*.5
.5R=20
R=20/.5
R=40 MPH. AGAINST THE WIND.
(50-40)/2=10/2=5 MPH IS THE SPEED OF THE WIND.
PROOF:
50-5=45 MPH SPEED OF THE ULTRA LIGHT.
40+5=45 MPH DITTO.