How about...How big does text need to be in order for you to be able to comfortably read it? (Compare using a quarter or other common object a certain distance

How about...How big does text need to be in order for you to be able to comfortably read it? (Compare using a quarter or other common object a certain distance away from you.) For example on the rift, text is readable when it's the size of a quarter ~3 feet away from me.