\[\boxed{\mathbf{441}.}\]
\[1)\ 15,63 + 4,4 = 20,03\]
\[2)\ 5,5 + 15 = 20,5\]
\[3)\ 6,19 + 2,71 = 8,9\]
\[4)\ 25,2 - 19,37 = 5,83\]
\[5)\ 12,35 - 6,3862 = 5,9638\]
\[6)\ 46,403 - 28,68 = 17,723\]