Question 696370
D=RT
3000=(R)6 RATE AGAINST THE WIND. 
R=3000/6
R=500 KPH. 
3000=(R)5 RATE WITH THE WIND.
R=3000/5
R=600 KPH. 
(600-500)/2
100/2=50 KPH. IS THE SPEED OF THE WIND.
500-50=450 ANS. FOR THE SPPD OF THE PLANE IN STILL AIR
400+50=450 DITTO.
PROOF:
3000=500*6
3000=3000
3000=600*5
3000=3000