2010-II-17

$\begin{array}{cl}
= & \dfrac{1}{2} \times 1 \\
= & 0.5 \text{ cm}
\end{array}$

由此，長方形的長的最小可能值

$\begin{array}{cl}
= & 12 – 0.5 \\
= & 11.5 \text{ cm}
\end{array}$

及其闊的最小可能值

$\begin{array}{cl}
= & 10 – 0.5 \\
= & 9.5 \text{ cm}
\end{array}$

所以，該長方形的最小可取面積

$\begin{array}{cl}
= & 11.5 \times 9.5 \\
= &109.25 \text{ cm}^2
\end{array}$