I should perhaps add…at low fuel levels the gauging was inaccurate ( in part due to fuel sloshing around in the tanks.)
On 11 (and 12) that caused a fuel “low level” light to come on earlier then perhaps expected and the timings you hear on the recordings were all based on the time that light illuminated, not from a quantity gauge. As a result of the low level light coming on early the fuel calls on both missions were a bit pessimistic, post flight it was generally reckoned Eagle landed with maybe 40-45 seconds of fuel in the tanks.
https://www.watchtime.com/featured/t...-moon-landing/
After Apollo 12 the tanks were modified with anti slosh baffles to reduce gauging/indication problems.
edit to add: It’s all very comprehensively covered here:
https://www.hq.nasa.gov/alsj/a11/a11.landing.html
and specifically the comments at the 102 hrs 42 min 35 sec point, which includes..
[Post-flight analysis indicated that Neil landed with about 770 pounds of fuel remaining. Of this total, about 100 pounds would have been unusable. As indicated in an unnumbered figure from page 9-24 in the Apollo 11 Mission Report, the remainder would have been enough for about 45 seconds, including about 20 seconds for an abort.]