This is more of a maths issue than excel, but thought I'd air it here for some assistance!
Original % £ Total Discount /New Total
1000 10.0% 100 900 11.11%
1000 15.0% 150 850 17.65%
1000 17.5% 175 825 21.21%
1000 20.0% 200 800 25.00%
1000 22.5% 225 775 29.03%
1000 25.0% 250 750 33.33%
In the above table we start with an original figure of £1000 in all cases. A percentage discount is the applied e.g. 10%. The original figure less the discount is shown in the next column - eg 10% of £1000 = £100. The next column shows the original £1000 less the discount of £100 = £900. If you then divide the discount by the new total you get a new percentage ie £100/£900 = 11.11% or 150/850 = 17.65%. This end percentage would be the figure needed to multiply the new total by in order to groos up to get back to the £1000.
In this case the constant is £1000. What I need to do is omit any total £ totals, and just keeping the percentages, create a formula in a cell which will give me the end percentage result. eg person inputs 10% into one cell, and I want another cell to return the answer 11.11%.
I do not want to use lookup tables as there are a vast amount of original percentages this could be for. I also do not want the £1000 referenced in the formula as this will be an unknown to the person entering the discount % at the time. What would be the formula required if for example the input cell was A1?
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