Extracting Data form repeat Group

1. What is the problem? Be very detailed.
I am working on a form where I am using repeat group for collecting household member's information. There I am capturing member's monthly income.
After that, I used index-repeat function to extract member's income outside of the repeat group in 15 separate variables(assuming that maximum household member should not exceed 15). Then I calculate the sum of income in 15 different variables (using syntax for 15 different condition in relevance.)
But, I need the sum in one variable. How can I get this?
2. What app or server are you using and on what device and operating system? Include version numbers.
ODK aggregate, SurveyCTO
3. What you have you tried to fix the problem?

4. What steps can we take to reproduce the problem?
Need the income sum of household members in one variable
5. Anything else we should know or have? If you have a test form or screenshots or logs, attach below.test.xlsx (20.6 KB)

ODK and SurveyCTO are not the same thing. If you are using SurveyCTO, you should get in touch with their support team.

Hi @Likhon,

The easiest way is to use sum() function. It works perfectly with ODK aggregate, but I have no idea about SurveyCTO.
For more details about sum function kindly have a look at this link Sum()
Kindly find attached file.test_Sum.xlsx (19.9 KB)
Best,
Yasser