\[\boxed{\mathbf{2.}\mathbf{368}}\]
\[7,02\ :7,8 = 70,2\ :78 = 0,9\]
\[64,5 - 0,9 = 63,6\]
\[72 - 64,5 = 7,5\]
\[477 - 152,6 = 324,4\]
\[6,88\ :8,6 = 68,8\ :86 = 0,8\]
\[16,3 - 0,8 = 15,5\]
\[11,49 - 5,73 = 5,76\]
\[513,23 + 89,28 = 602,51\]