What are the dimensions of an approach plate plan view in nautical miles?
FYI, what you're trying to do is called "georeferencing."

The scale for each plate is whatever is required to fit in all the relevant information without wasting space. Therefore, to properly geo-reference each plate, you will need to identify at least two points (e.g. CUTIS and CFVGK in this case), look up their lat/long in the published tables, and calculate the scale from there.

Note that some charts (more commonly SIDs and STARs than IAPs) are explicitly marked "NOT TO SCALE", which means this tactic can't work at all. And even some charts that are mostly to scale may have a few elements that aren't, usually transition fixes or navaids, marked by a double zigzag.