12 is an integer and so already rounded to a hundredths (and more).
12
983.64
2.590 rounded to the hundredths is 2.59
It is already rounded to the nearest hundredths.
346.77
64.448 rounded to the hundredths place is 64.45
It is 7.12 when rounded to the nearest hundredths
0.99 is already rounded to the nearest hundredths.
37.68
62.71
2.847 rounded to the nearest hundredths would be 2.85.
0.18 is already rounded to the hundredths place !