\[\boxed{\mathbf{Вариант\ 1.}}\]
\[\boxed{\mathbf{1.}}\]
\[807.\]
\[\boxed{\mathbf{2.}}\]
\[900 - 1 = 899\]
\[Ответ:\ 899.\]
\[\boxed{\mathbf{3.}}\]
\[300 + 58 = 358\]
\[Ответ:358.\]
\[\boxed{\mathbf{4.}}\]
\[4\ сот.\ 2\ дес. = 420\]
\[Ответ:420.\]
\[\boxed{\mathbf{5.}}\]
\[\boxed{\mathbf{6.}}\]
\[\boxed{\mathbf{7.}}\]
\[\boxed{\mathbf{8.}}\]
\[Ответ:3.\]
\[\boxed{\mathbf{9.}}\]
\[60 \cdot 9 = 540\]
\[640 - 540 = 100\]
\[Ответ:на\ 100.\]