If you don't mind predefining your keys:
my $key1 = sprintf "%.2f", 45.20;
my %ITEMS = ( $key1 => 'item 1');

[download]
This will work. I tested it as follows: 
$key1 = sprintf "%.2f", 52.30;
my %ITEMS = (
    $key1 => 'item 1',
    45.25 => 'item 2'
);
my $input = <STDIN>;
chomp ($input);
if (exists $ITEMS{$input}) {
    print $ITEMS{$input} . "\n";
}

[download]
It printed "item 1" when I entered 52.30.

In reply to Re: Floats with trailing zeros as a hash key by cbro
in thread Floats with trailing zeros as a hash key by hardburn

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