The constructor requires a number and won't accept a scalar; otherwise, I think that you did a good job on it. 
#!/usr/bin/perl

use strict;
use warnings;
use Test::More tests => 11;
use Math::BigInt upgrade => 'Math::BigFloat';
use Math::BigFloat;

BEGIN {
    use_ok( 'Math::BigInt'   );
    use_ok( 'Math::BigFloat' );
}

note 'Math tests';

my $bf = 'Math::BigFloat';

for ( my $i = 1; $i < 1000000000; $i *= 10 ) {
    $bf = Math::BigFloat->new(1); 
    $bf->precision(-2);
    my $xpect = 
       ($bf > 1 ? '3' x (scalar($bf->length) - 1) : 0)
       . '.33';
    is $bf->bdiv(3), $xpect, $i . ' / 3 = ' . $xpect;
}

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In reply to Re: Another Math::BigFloat precision question by Khen1950fx
in thread Another Math::BigFloat precision question by Seba

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