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Confusion on adding percentage of cost to that cost.
Posted:
Jul 10, 2005 10:05 PM


Here's my view. Say I have a product with my cost of $100.00
I want to add 28% to that. I think I should end up at $128.00.
My math is simply $10.00*1.28 = $12.80
However, I have had someone else tell me that I'm wrong and need to do the following.
First. 100x=y Second. 100/y=z Third. A*z=$$$.$$
So, First. 10028 = 72 Second. 100/72 = 1.38888889 Third. 10*1.3889 = $13.89
Now to me this person is crazy. I mean I sold stuff for years and sales tax wasn't that complicated. If something was $10.00 + %5.75tax, the total is $10.58.
Not 1005.75 = 94.25, 100/94.25 = 1.061007, $10.00*1.061007 = $10.61
Why would he think that he's correct? Is it some accounting practice, but not real world practice? Or maybe something a person not originally from the US would have learned?
Thanks for clearing this up.
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