Question 456890

Investment I	7.00%		per annum	$x		
Investment II	4.00%		per annum	$y			
x+y=28000	------------------------1				
7.00%x+4.00%y=$1,720.00			
Multiply by 	100							
7x+4y=$172,000.00		--------2	
Multiply (1) by	-7						
we get									
-7x-7y=	-196000.00			
Add this to (2)									
-3y=-$24,000.00			
divide by -3							
y=$8,000.00	investment at 	4.00%
Balance	$20,000.00	investment at 	7.00%

CHECK
20000 @ 7%=$1,400.00
8000 @ 4% = $320.00
TOTAL Interest $1,720.00