Question 552043
Plane	speed=	x	mph						
wind	speed=	y	mph						
with wind speed=		(x+y) 							
against wind speed		(x-y) 							
d=	2800		=						
2800	/	(x+y) 		2.5					
divide by 	2.5		=	1					
1120	/	(x+y) 							
(x+y) 	=	1120	............1						
d=	=	2800	against 	wind					
2800	/(x-y)=	3.5							
divide by 	3.5								
800	/(x-y)	=	1						
x	-		y	=	800	.............2		
add up (1) & (2)									
2	x	=1920							
/	2								
x=	960	mph	speed of	Plane	in still air				
plug value of x in (1)									
we get 	y= 	160	mph	speed of	wind