Question 580604
Son's age	x												
Father's age			3      	x									
	12	years later											
Son's age	x	+	12										
Father's age		3    	x	+	12								
Father's age	2      	times older											
	3    	x	+	12	=	2    	(	x	+	12	)		
	3    	x	+	12	=	2    	x	+	24				
		1	x			=	24	-12					
		x	=	12	Son's age								
	3    	x=	36	years		Father's age