Final answer:
The nominal size of 3/4 x 5 1/2 lumber is the initial cut size, not the final, which is typically smaller due to drying and finishing, with actual dimensions being approximately 1/2 x 5 1/4 inches.
Step-by-step explanation:
The nominal size of 3/4 x 5 1/2 lumber refers to the size of the lumber when it is first cut, before it is dried and finished. This is different from the actual size of the lumber, which can be smaller due to the drying process and planning.
For instance, a piece of lumber with a nominal size of 3/4 x 5 1/2 inches will typically have an actual size of approximately 1/2 x 5 1/4 inches. The shrinking happens due to the moisture loss and the finishing process.