\[\boxed{\mathbf{1.}\mathbf{42}}\]
Пояснение.
Решение.
\[\textbf{а)}\ 30\ :20 \cdot 100 = 150\]
\[\textbf{б)}\ 45\ :20 \cdot 100 = 225\]
\[\textbf{в)}\ 100\ :20 \cdot 100 = 500\]
\[\textbf{г)}\ 0,2\ :20 \cdot 100 = 1\]
\[\textbf{д)}\ 0,7\ :20 \cdot 100 = 3,5\]
\[\textbf{е)}\ 5,5\ :20 \cdot 100 = 27,5\]