\[\boxed{\mathbf{3.}\mathbf{227}}\]
\[\textbf{а)}\ 25 \cdot 3 = 75\ :15 = 5 + 29 =\]
\[= 34\ :17 = 2\ \]
\[\textbf{б)}\ 15 \cdot 4 = 60 + 16 = 76\ :19 =\]
\[= 4 - 4 = 0\]
\[\textbf{в)}\ 100\ :25 = 4 \cdot 17 = 68\ :2 =\]
\[= 34 + 26 = 60\]
\[\textbf{г)}\ 16 \cdot 3 = 48 - 12 = 36\ :12 =\]
\[= 3 \cdot 23 = 69\]
\[\textbf{д)}\ 54\ :18 = 3 + 27 = 30\ :15 =\]
\[= 2 \cdot 29 = 58\]