1 2 3 VONG THI THU 13 NAM 2010 4 5 (123,5 X 10 :9) 6 2mat116+542 la1 mat + 8 la3mat= 666 hop nho tong so mat son la 1485 mat 1485 – 666 = 819 mat khong duoc son (1434214EB363907) 7 8