Hi Abdus,

Insert the constant sum question first and then without leaving the page break add the multiple choice question as Dont know. 

Using JS do the validation.

I want to set constant sum with Don’t know(exclusive) option. Here brands are coming from previous selection. Please help to set up..

Example-
Q4 is a multiselect question, where i select option A,B,C
 

Then next question shows like 

Now, i want to select either “Don’t know” or input values for A,B,C. The input value for A,B,C must be 100.
How can i validate Q2, as number of options based on previous question Q4.

It needs a custom JS code to fix this. 

can you please help me, sharing the code