<PRE><B>Question 519971</B>
	--------price	----------------	quantity									
Coffee I	90	----------------			30	pounds						
coffee II	20	----------------			x	pounds						
Mixture	40	----------------	30	+	x	pounds						
												
90*30+20x=40(30	+x)
2700+20x=1200+40x				
20x+-40	x=1200	-	-2700				
-20	x	=	-1500									
/	-20											
x	=	75										
		75	pounds		of	$20	coffee II				
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