Summing the values of 3 columns apart

[bkbkbk01]

I have tried to use =SUM(IF(MOD(COLUMN(B3:O3),3),0,B3:O3)) to calculate the value in every 3 columns (B3, E3, H3......) and when I input (COLUMN(B3:O3),3), the value will be the sum of C3, F3, I3.... However when I input 2 (COLUMN(B3:O3),2), the value will be the sum of B3, D3, F3.....

How can I correct the formula so that I can get the value of the sum of B3, E3, H3......

Thank you!

*I also try 4 and I get the values of D3, H3....

[#2 · Accepted solution]

@bkbkbk01 Try it this way.

=SUMPRODUCT((MOD(COLUMN(B3:O3),3)=2)*(B3:O3))

The MOD(----, 3) function returns a value of 2 for columns B,E,H etc.

[#3]

FINALLY ITS WORK!!!!!
Thank you so much!!!