Answer
$5\;cm\times 1\;cm$.
Work Step by Step
The number of spaces for the length of the rectangular hole $=10$.
Let the actual measurement is $=x$.
$\Rightarrow \frac{scale \;measurement \;1}{actual\;measurement\;1}=\frac{scale \;measurement \;2 }{actual\;measurement\;2}$
$\Rightarrow \frac{1\;space}{0.5\;cm}=\frac{10\;spaces}{x}$
Cross multiply.
$\Rightarrow x=5\;cm$.
The length is $=5\;cm$.
The number of spaces for the width of the rectangular hole $=2$.
Let the actual measurement is $=x$.
$\Rightarrow \frac{scale \;measurement \;1}{actual\;measurement\;1}=\frac{scale \;measurement \;2 }{actual\;measurement\;2}$
$\Rightarrow \frac{1\;space}{0.5\;cm}=\frac{2\;spaces}{x}$
Cross multiply.
$\Rightarrow x=1\;cm$.
The width is $=1\;cm$.
Hence, the dimensions are $=5\;cm\times 1\;cm$.
