<PRE><B>Question 1137307</B>
Nickola swam at a rate of 2 ​km/hr --- let time be x hours

and ran at a rate of 11 ​km/hr -------- let time be y hours

total distance traveled of  68.5 km. Distance = speed x time

So  2x+11y =68.5 .........(1)

 he completed the race in 9.5 ​hours, 

Time swimming + time running = 9.5 hours

x+y=9 ................ (2)

time swimming	x	hours										
time running	y	hours										
												
	x	+		y	=	9.5	.............1					
2	x	+	11	y	=	68.5	.............2					
Eliminate y												
multiply (1)by 		-11										
Multiply (2) by		1										
-11	x		-11	y	=	-104.5						
2	x		11	y	=	68.5						
Add the two equations												
-9	x				=	-36						
/	-9											
x	=	4		    							
plug value of 			x	in (1)								
	x	+		y	=	9.5						
4		+		y	=	9.5						
				y	=	9.5		-4				
				y	=	5.5						
			
time swimming	4    	hours										
time running	5 1/2	hours										




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