Question 525995
7%--------------x
8%--------------(x+y+4000)
12%-------------y

x+x+y+4000+y= 50000
2x+2y+4000=50000
2x+2y=46000
/2
x+y=23000..............(1)

7x+8(x+y+4000)+12y= 4770 *100  ( the % is converted by multiplying by 100)

7x+8x+8y+32000+12y=477000
15x+20y=477000-32000
15x+20y=445000
/5
3x+4y=89000................(2)

1	x	+	1	y	=	23000	.............1	
3	x	+	4	y	=	89000	.............2	
Eliminate y								
multiply (1)by 		-4						
Multiply (2) by		1						
-4	x		-4	y	=	-92000		
3	x		4	y	=	89000		
Add the two equations								
-1	x				=	-3000		
/	-1							
x	=	3,000.00						
plug value of 			x	in (1)				
1	x	+	1	y	=	23000		
3000		+	1	y	=	23000		
			1	y	=	23000		-3000
				
7%--------------x= $3,000
8%--------------(x+y+4000)= $27000
12%-------------y= 20000

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