Question 719965
x+y=300.................(1)

0.1x+3y=78
multiply by 10
x+30y=780................(2)

1	x	+	1	y	=	300	.............1	
Total value								
1.00	x	+	30.00	y	=	780.00	.............2	
Eliminate	y							
multiply (1)by		-30.00						
Multiply (2) by		1.00						
-30.00	x		-30.00	y	=	-9,000.00		
1.00	x	+	30.00	y	=	780.00		
Add the two equations								
-29.00	x				=	-8,220.00		
/	-29.00							
x	=	283.45						
plug value of			x	in (1)				
1.00	x	+	1.00	y	=	300.00		
283.45		+		y	=	300.00		
				y	=	300.00		-283
				y	=	16.55		
				y	=	16.55