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Topic: Confusion on adding percentage of cost to that cost.
Replies: 7   Last Post: Jul 13, 2005 6:45 PM

 Messages: [ Previous | Next ]
 strommsarnac@gmail.com Posts: 2 Registered: 7/14/05
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. 100-x=y
Second. 100/y=z
Third. A*z=\$\$\$.\$\$

So,
First. 100-28 = 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 100-5.75 = 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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Date Subject Author
7/10/05 strommsarnac@gmail.com
7/11/05 Bob
7/11/05 J. J. Sroka
7/11/05 ticbol
7/11/05 strommsarnac@gmail.com
7/12/05 ticbol
7/13/05 Kevin Killion
7/13/05 Rob Morewood