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In this example, our fist item has a sell price of $10.2 which is 40% mark up. To update it to 50% mark up, we can calculate by $10.00 X 60% + Cost Ex tax = $16.32. If you're using formulas to calcuate the new markup, make sure to paste the data as values prior to importing.
6. Save the updated file and go back to Inventory → Supplies → but this time, select Import.
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