Create a simple table of two columns. The first column could be the
concentration in the desired units i.e. micrograms per litre. The second
column could be the inhibitory effect from 0% to 100%. Then you can use
VLOOKUP() to find the approximate 50% level.
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Gary''s Student


"Fred Smith" wrote:

First you need to tell us what IC50 is.

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Regards,
Fred


"jc33" wrote in message
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