<PRE><B>Question 872880</B>
plane 	speed	x	mph									
wind  	speed	20	mph									
..												
against 	wind  	x-	20									
with	wind  	x+	20									
..												
against	wind  	4	hours									
with 	wind  	3	hours									
Distance is same.  D=r*t												
4	(	x	-	20	)	=	3	(	x	+	20	)
4	x	-	80			=	3	x	+	60		
4	x	-	3	x	=		80	+	60			
1	x				=		140					
/	1											
x				=		140	mph					
plane 	speed	=	140	mph								
</PRE>