<PRE><B>Question 500158</B>
percent	percent	----------------			quantity								
Saline I	4	----------------			x	liters							
Saline II	7	----------------	3	-	x	liters							
Mixture	6.80%	----------------	3										
													
4x+7(3-x)=6.8*	3	
													
4x+21-7x=20.4			
4x-7x=	20.4	-	21			
-3x=	-0.6							
/	-3												
	x=0.2	liters	4.00%		Saline I	
	2.8	liters 	7.00%		Saline II	
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