Question 1007654

Boat speed	speed	=x	mph					
stream	speed	=y	mph					
against 	stream	2 2/3	hours					
with 	stream	2	hours					
								
Distance with	stream	100	miles		distance against	stream	100	
t=d/r	against	stream	(x-y)					
100    	/	(	x	-	y	)=	2 2/3	
								
2 2/3	x	-	-2 2/3	y	=	100    	....................1	
with	stream	(x+y)						
100    	/	(	x	+	y	)=	2    	
2    	(	x	+	y	)	=	100    	
2    	x	+	2    	y	=	100    	...............2	
Multiply (1) by	2    							
Multiply (2) by	2 2/3							
we get	2    							
5 1/3	x	+	-5 1/3	y	=	200    		
5 1/3	x	+	5 1/3	y	=	267    		
10 2/3	x	=	467    					
/	10 2/3							
x	=	43 3/4	mph					
								
plug value of x in (1)				y				
2 2/3	x		-2 2/3	y	=	100    		
116 2/3			-2 2/3	-116 2/3	=	100    		
-2 2/3	y	=	100    					
-2 2/3	y	=	-16 2/3	mph				
	y	=	6 1/4					
Boat speed	43 3/4	mph						
stream	6 1/4	mph						
								
CHECK								
x+y=	50    							
X-y=	37 1/2							
100    	/	(	43 3/4	+	6 1/4	)=	2    	
100    	/	(	43 3/4	)-	6 1/4	=	2 2/3