Potency calculations active ingredients

Quality Assurance
1

Dear Sir
i would like to know brief about Potency calculations active ingredients .

2

Potency also reffered as API calculation,

Actual quantity of active to be dispensed as per actual assay calculation
and it is done by assay on dried or asis basis and nil LOD/ residual solvents :

% Potency= API qty per lot
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% Purity

% Purity = API qty per lot x 100 x 100
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Assay on dried basis X (100- %LOD)

3

How can I calculate diluent based on potency of api