Hp laserjet 3055 scans larger than print area

When you place a document for scan, you must select the portion you want to be scanned.

You must also set the resolution which is set to 300 by default, if you want a actual size then set the resolution to 75, which is 3% larger then actual image.

It will reduce size in KB or MB of your image and it will be exact size.

Similarly, when you want to print, you must select option "Exact Fit" and print your document.

Everything will be normal.

Cheers