Question 552824
boat  	speed	=x	mph				
current  	speed	=y	mph				
against current x-y		1.50	hours				
with current x+y		1.00	hours				
							
Distance = same=		6	miles				
t=d/r							
6/(x-y)=	1.50
1.5(x-y)=	6.00
1.5x-1.5y=	6	....................1
6/(x+y	)=	1.00
1.00(x+	y)=6
1.00x+1.00y=6	...............2
Multiply (1) by 	1.00						
Multiply (2) by	1.50						
we get							
1.5x-1.5y=6	
1.5	x	+	1.5	y	=	9	
3	x	=	15				
/	3						
x 	=	5	mph