Greatest possible error for 4and1/8in.

Question

Greatest possible error for 4and1/8in.

Answer 1

need a lot of detail as to what you are measuring and with what.

without that, the greatest error would be either - 4 1/8 and + infinity. In other words, any number is possible.

Answer 2

4-1/8" means you can measure down to the nearest 1/8 of an inch.  Measurements above or below 4-1/8 are either rounded up to 4-1/4" or down to 4".  

Assuming a person measures properly, the greatest possible error is one half of 1/8" or 1/16".