Question 445889
Adult			x	Numbers				
Child		------------	y	Numbers				
x+y=600	.............1	
20x+10y=9800	.............2	
Eliminate y							
multiply (1)by 	-10						
Multiply (2) by	1						
-10x-10y=-6000		
20x+10y=9800		
Add the two equations								
10x=	3800		
/10							
x=380						
plug value of 			x	in (1)				
x+y=600		
380+y=600		
y=600	-380
y=220