Huh. You're absolutely correct. Floating point match is notoriously problematic when doing rounding. It's just the nature of doing floating point arithmetic on a binary processor.

You could take mwah's solution. Or, you could convert everything to integers. So, instead of working in dollars, you work in cents. 

my $price = 1795; # Cents, not dollars
my $qtyx = 3; # Amount, not a price.

my $cost = $price * $qtyx;

my $cost_to_display = $cost / 100;

[download]
And that works when tested.
My criteria for good software:
  1. Does it work?
  2. Can someone else come in, make a change, and be reasonably certain no bugs were introduced?

In reply to Re^3: Multiplication problem by dragonchild
in thread Multiplication problem by John Vanbeek

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