up the garden path...

[chapeau]

Agree entirely.

Any of the .5 can belong to two whole numbers, and that can't be right.

 

[empip]

5.0m :- A zero following decimal point implies accuracy to two significant figures

Measurements could be between 4.95m and 5.04m

My answers :-
4.95m at two sig' fig's rounds up to 5.0m
5.04m at two sig' fig's rounds down to 5.0m

Or something like that...

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