Question 510872
Boat speed	speed	=x	mph					
current speed 	speed	=y	mph					
against wind x-y		4.00	hours					
With current x+y		3.00	hours					
								
Distance = same=		96	miles					
t=d/r								
96	/	(	x	-	y	)=	4.00	
4	(	x	-	y	)	=	96.00	
4	x		-4	y	=	96	....................1	
96	/	(	x	+	y	)=	3.00	
3.00	(	x	+	y	)	=	96	
3.00	x	+	3.00	y	=	96	...............2	
Multiply (1) by 	3.00							
Multiply (2) by	4.00							
we get								
12	x	+	-12	y	=	288		
12	x	+	12	y	=	384		
24	x	=	672					
/	24							
x 	=	28	mph					
								
plug value of x in (1)								
4	x		-4	y	=	96		
112			-4	y	=	96		
-4	y	=	96	-112				
-4	y	=	-16					
	y	=	4	mph