Question 449120
------	percent	----------------	quantity										
Alcohol I	90----------------90	liters			
Alcohol II	50----------------x liters
Total	80---------------90+x	liters
													
90*90+50	*x=80(90+x)
8100+50x	=7200+80x					
50x-80x=	7200-8100					
-30x=-900								
/		-30							
x=30	liters	50	%	alcohol II