Measure (and cost) of returning "exactly the same" result unspecified, a pedant would note it's pure luck and coincidence that for 9 intervals these functions indeed seem to always return the same. For a simple case of 6 intervals:

~$ perl -E 'say 4 if    0.8333333333333333 < 5/6'
4
~$ perl -E 'say int 6 * 0.8333333333333333'
5
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For maybe general case of 100 intervals, playing with Data::Float (and from similar experiment literal number above came from):

~$ perl -MData::Float=nextdown -E '$n=100; for(1..$n){say if $_-1 != i
+nt $n*nextdown $_/$n}'
5
10
17
20
23
34
40
46
67
68
80
81
92
93
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