Multi-select Text

Thanks Mark for the response.
I will give an example:
We sell very specific machines which depend on the number of products the machines will have to produce; per day and per week.
The (commercial) user will have to fill in a numeric field with the number of products per week.
We don't know how many days the machine will work per week. Most of the time it is 4 days.
The field I want to create should give the user a choice between; [how many products per week]/4, and manual classification.
A simple way I thought of is a yes or no question (the machine will produce [how many products per week]/4 per day). Otherwise to display and ask to fill in another field. This will need to be done for about 13 fields, which means at least 26 new fields. This is not optimal from a dataset perspective.
My question is about the possibilities of a "multi-select field" combined with a formula or another field.

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Hamza GHALLABI
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