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You have a few options:
-Code (script) component in Scripting library (basically writing your own component)
-Formula component in Calc library
-Use repeated subtraction in a loop to get modulo the long way
I can help you out with any of these ways if needed.
I would like to perform a mod 10 operation in a workflow, I cannot find a components for this in the Math group. Is there any components like this at all in the workflow libraries?