The pattern is (Column1 + Column3) / Column2 = a constant. For Row 1: (13+71)/16 = 5.25. For Row 3: (4+14)/10=1.8. Let's try the hint: $(13+19)=32/4=8$. The pattern seems to be $(R1C1 + R1C2)/R3C1 = R1C3$. The source hint is unclear, but the answer is 20.