How to identify those names shared by two groups and do a sum-up?

**zjianguk** · 03-14-2013, 11:38 AM

Hi Sir,

I'm looking for a big help to solve this tricky question. Basically, there are two groups of courses. Some courses are shared by both courses. Each course has a weighting in a group.

Now the question is: to use a formula to get the total absolute difference of weightings for those courses shared by both groups?

I made a sample and attached here.

Hope this can be solvable.

**Fotis1991** · 03-14-2013, 11:57 AM

This should be one way to do this.

**zjianguk** · 03-14-2013, 12:05 PM

Originally Posted by Fotis1991

This should be one way to do this.

Thanks, Fotis1991. For my case, due to the difficulty of creating extra columns, I am a bit struggling to try to put everything together in a single formula, though looks not easy

**Fotis1991** · 03-14-2013, 12:11 PM

I tried to keep it simple.

**zjianguk** · 03-14-2013, 12:32 PM

Hi, Fotis, I'm trying to see if I can put together your separate formulas.

I very appreciate it if there can be an interesting answer to this question.

**zjianguk** · 03-14-2013, 12:53 PM

Hi Fotis, just wondering why this formula does not work for the sample:

=SUM(IFERROR(INDEX($G$3:$G$8,MATCH(A3:A8,$F$3:$F$8,0)),"")), confirmed with Ctrl + Shift + Enter