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Next, you must turn the formula field into a trigger and create conditions that make it impossible for the signer to complete the form until the expression is made true (X + Y + Z = 100). To do so, you need to create two new required text fields, assign them the exact same data label, give them conflicting validations, and make them conditional to the formula field (make these fields appear when trigger = 0).
In order to create conflicting validations, you need to select Custom Validation and use a regex pattern. The example below only accepts digits 0-4 in the first field and digits 5-9 in the second.
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