\[\boxed{\mathbf{3.}\mathbf{262}}\]
\[5506 - 5415 = 91\]
\[139 - 91 = 48\]
\[321 - 318 = 3\]
\[3 + 24 = 27\]
\[16\ 524 - 16\ 486 = 38\]
\[\textbf{г)}\ 9984\ :48 - 14\ 283\ :69 =\]
\[= 208 - 207 = 1\]
\(д)\ 1560\ :(52 \cdot 36 - 20 \cdot 91) =\)0
\[= 1560\ :52 = 30\]
\[91 \cdot 20 = 1820\]
\[1872 - 1820 = 52\]
\[247\ 100 - 47\ 000 = 200\ 100\]
\[200\ 100\ :300 = 2001\ :3 = 667\]