\[\boxed{\mathbf{92.}}\]
\[\textbf{а)}\ 200 + 40 = 240\]
\[300 + 5 = 305\]
\[410 + 100 = 510\]
\[\textbf{б)}\ 5 \cdot 4 + 100 = 20 + 100 = 120\]
\[100 + 6 \cdot 5 = 100 + 30 = 130\]
\[5 \cdot 8 + 300 = 40 + 300 = 340\]
\[200 + 40\ :5 = 200 + 8 = 208\]
\[21\ :3 + 300 = 7 + 300 = 307\]
\[100 + 63\ :9 = 100 + 7 = 107\]