Yeah, sprintf is most probably the right way to go. Just a possible example under the Perl debugger: 
  DB<1> print sprintf "%.2f", 10/3;
3.33

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Of course, in that specific example, I could have made it simpler: 
  DB<2> printf "%.2f", 10/3
3.33

[download]
Having said that, there are some very rare edge cases where the results are somewhat unexpected because of specific IEEE standard rounding rules. Consider this: 
$ perl -e 'printf "%.2f\n", $_/20 for 1..10'
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50

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This looks completely fine. Now just round it to one less digit: 
$ perl -e 'printf "%.1f\n", $_/20 for 1..10'
0.1
0.1
0.1
0.2
0.2
0.3
0.3
0.4
0.5
0.5

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This looks a bit awkward, doesn't it? 0.05 and 0.15 are rounded to the same value, which is somewhat contrary to common sense rounding. There are very good reasons why IEEE standards chose that type of rounding, but I had once to write my own custom rounding subroutine for a legacy currency to Euro conversion, because the client would not accept this type of rounding as being correct.

In reply to Re: Rounding numbers by Laurent_R
in thread Rounding numbers by Dr Manhattan

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