[X4U] Tiger's Calculator.app no longer does percentages?

Neil Lists at mac.com
Sat Nov 26 16:05:55 PST 2005


on 11/26/05 6:07 PM, John Baltutis wrote:

> Color me confused, but 15% = 0.15, which when added to 28.05 = 28.2 (at
> least that's consistent with what I learned in school 58 years ago). To do
> what you want, simply use 28.05 * 1.15 = 32.2575.

The reason your are confused is because "15% of" is the same thing as "0.15
times,"  but the only time 15%=0.15 is when it is 15% of 1.0.   When your
dinner bill comes to $127 do you leave a dime and a nickel as a 15% tip (ie.
$.15)?

I think the original example is ambiguous because it didn't specify the
"of."  One very reasonable assumption would be that the 15% mentioned in the
equation is 15% of the 28.05.  I'm not sure that I would consider a
calculator broken just because it didn't make that assumption, but it makes
no sense at all for the calculator to assume that it's 15% of 1.  Where did
the 1 come from?  Thin air?

> If Panther's calculator works the way you described, then, IMHO, it's the
> one with the error, not the one in Tiger.

I disagree.  Panther's calculator made an arguably more reasonable
assumption than Tiger's did.  I'm not sure that I would say one is clearly
correct though. 



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