What they are saying ^^^^^^^
I am assuming we are talking decimal minutes here and not seconds of
arc. In which case write it as 54*16'.879 N , not 54.16.879 N ( I use * for 'degrees' on the puter... to much fuss making a proper 'degree' symbol
)
Let's consider latitude first.....1 minute of
arc is 1 nautical mile .... the first decimal place is 170 metres.... the second decimal place is 17 metres.... the third decimal place is 1.7 metres..... which end of the
boat are we talking about here ?
With longitude the numbers are smaller still esp in your latitude.
In the ocean whole minutes are all you need, coastal
navigation use the first decimal place. Only in logging narrow passes,
anchorages and harbour features do you need to bother with the second decimal place. The use of the 3rd decimal place shows a lack uf understanding of what you are working with..