Given:
The given figure represents the original parallelogram and the reduction.
To find:
The length of side A in the new parallelogram.
Solution:
We know that the original figure is always similar to its reduction. So, both parallelograms are similar to each other.
The corresponding sides of similar figures are proportional.
[tex]\dfrac{45}{18}=\dfrac{5}{A}[/tex]
[tex]45\times A=5\times 18[/tex]
[tex]45A=90[/tex]
Divide both sides by 45.
[tex]A=\dfrac{90}{45}[/tex]
[tex]A=2[/tex]
The length of side A in the new parallelogram is 2 cm. Therefore, the correct option is A.