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What code should I put in the question validation text of a multiple numerical question to ensure the value adds up to the number a respondent entered in q1a

Currently trying sum(self.NAOK)=={q1a}

Hi,
this is wrong syntax.
You see that the question validation equation automatically surrounds with curly brackets
 

You create something like {sum(self.NAOK)=={q1a}}
So this equation should be
sum(self.NAOK)==q1a

BTW: Instead of the question validation equation you can use the setting
 
Just enter q1a

Joffm