Decimal arithmatic, was Re: Python GUI app to impress the boss?

[Kim Petersen]

Grant Edwards wrote:
> In article <memo.20021001113235.1724A at a.a>, Mark Charsley wrote:
> 
> 
>>>Usually, in the "canned" systems I've seen, those 3 for a 
>>>buck deals are supported by allowing three to five decimal
>>>places rather than just two for amounts.  Results come out
>>>much as you are expecting there.
>>
>>The system a previous company wrote said that "if they've bought 3 
>>40p items these give them a discount of 20p".
> 
> 
> But, standard practice around here is that the "3 for a dollar"
> price is good on quantities of less than three.  (IOW the unit
> price is 1/3 dollar).  I have seen instances where you have to
> buy 3 to get the discount but IME that's rare.

(assuming IME is In My Environment) might be - but around here - All 
shops (with possible exceptions (i've never seen it)) sell only 
(multiple) quantities of 3 at the discount *even* if 2 will sell at a 
higher price....

>