\[\boxed{\mathbf{2}\mathbf{.}\mathbf{167}}\]
\[\textbf{а)}\ 15 \cdot 6 = 90\ :18 = 5 \cdot 19 =\]
\[= 95 + 6 = 101\]
\[\textbf{б)}\ 88 - 19 = 69\ :23 = 3 \cdot 15 =\]
\[= 45 + 55 = 100\]
\[\textbf{в)}\ 100 - 19 = 81\ :3 = 27 + 23 =\]
\[= 50 \cdot 4 = 200\]
\[\textbf{г)}\ 80 - 16 = 64\ :8 = 8 \cdot 11 =\]
\[= 88 + 22 = 110\]
\[\textbf{д)}\ 60 - 11 = 49\ :7 = 7 \cdot 15 =\]
\[= 105 - 25 = 80\]