A Lieberman wrote:

If I am assigned an altitude of 5000, does this allow me from 4900 to
5100 or does it mean that I stay within 4950 to 5050?

If you're assigned 5,000 and you're actually at 4,901, you're within 100' of
your assigned altitude.

George Patterson
Battle, n; A method of untying with the teeth a political knot that would
not yield to the tongue.