Answer :

16.207
  6.900
16.190
16.260
just add zeroes at the back of the some numbers to make it even with others.
look at the first digit of the number.
we know that 6.9 is the last one since it is the smaleest.
lets compare other three numbers.
16.207⇒this goes second
16.190⇒this goes third
16.260⇒this goes first
and
6.900 goes last so,
16.26
16.207
16.19
6.9

HOPE IT HELPS!!