§ Задание 67
\[\boxed{\mathbf{67}\mathbf{.}}\]

\[\textbf{б)}\ 5 + 45 - 39 = 50 - 39 = 11\]
\[90 - (3 + 54) = 90 - 57 = 33\]
\[100 - (2 + 68) = 100 - 70 = 30\ \ \mathbf{\text{\ \ }}\]
\[\boxed{\mathbf{67}\mathbf{.}}\]

\[\textbf{б)}\ 5 + 45 - 39 = 50 - 39 = 11\]
\[90 - (3 + 54) = 90 - 57 = 33\]
\[100 - (2 + 68) = 100 - 70 = 30\ \ \mathbf{\text{\ \ }}\]