\[\boxed{\mathbf{3.}\mathbf{188}}\]
Пояснение.
Решение.
\[\textbf{а)}\ 36 \cdot 101 = 36 \cdot (100 + 1) =\]
\[= 36 \cdot 100 + 36 \cdot 1 =\]
\[= 3600 + 36 = 3636\]
\[\textbf{б)}\ 22 \cdot 25 = (20 + 2) \cdot 25 =\]
\[= 20 \cdot 25 + 2 \cdot 25 = 500 + 50 =\]
\[= 550\]
\[\textbf{в)}\ 16 \cdot 99 = 16 \cdot (100 - 1) =\]
\[= 16 \cdot 100 - 16 \cdot 1 =\]
\[= 1600 - 16 = 1584\]
\[\textbf{г)}\ 45 \cdot 18 = 45 \cdot (20 - 2) =\]
\[= 45 \cdot 20 - 45 \cdot 2 = 900 - 90 =\]
\[= 810\]