I need a way to calculate the sum of 2 digit number in a cell to another cell, for example:
A1 → → B1
24 <- 2+4 = 6
56 <- 5+6 = 11
21 <- 2+1 = 3
32 <- 3+2 = 5
And so… on. I am using Libreoffice calc.
Thank you
One way; in B1
=MID(A1,1,1)+MID(A1,2,1)
and drag down as far as you need. Note: this will only work for a two digit number in A; it should be trivial to alter it for more digits.
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Yes, it works fine, Thank you. Only little problem is when a cell has a 2 digit starting with 0, it shows ### but I can live with that.
Thank you very much.
The ### usually means the cell is not wide enough to display the contents. Try widening the cell and see what happens.
The display oveflow reported by ### surely was caused by a #VALUE! error. As long as your “two digits” actually are numbers in the technical sense they won’t return leding zeros if treated the way @robleyd suggested. You need to make the entered pair of digits a text.
=SUMPRODUCT(VALUE(MID(TEXT(A1;REPT(“0”;14));ROW(INDIRECT(“A1:A14”));1))) should return the correct sum of digits for integers of up to 14 digits (leading zeros included) independent of the type under Calc.
Yes, it actually says #VALUE! when I increased the width of the column and the formula above (the bigger one) works. 
Thank you
Hi all, I want to do something like this, lets see i got number A1=6, B1=7 then sum in C1=13, i want A2=1 and B2=3 then C2=4
@Kevexcel: I cannot see any alikeness concerning your appended question and the original one.
What you asked for is achieved by the most basical formula you can have in a spreadsheet.
Put the formula =A1 + A2 into cell C1 and fill it down as far as needed (using the drag handle e.g.)
If you dislike the zero values returned for empty cells, use =IF(OR(A1="";B1="");"";A1+B1) or probably =IF(A1&B1="";"";A1+B1) if you want to accept one empty operand.
@Kevexcel: If I misunderstood you, please create a new question and explain in detail what you want to achieve. Don’t miss to read Guidelines for asking first.
Hi Lupp! Thanks for your respond.
I mean A1=6, B1=7 then C1=13, I want split that 13 to A2=1 and B2=3 then i will sum A2 and B2 equal 4 in C2
I do not understand this clearly beyond the single example.
If your intention is actually to get the second-order digit-sum then the document and the link you find in my answer below should meet your needs. Otherwise I cannot help without a clear explanation in terms leaving the example behind.
Where do A1, B1 come from? Are they assuerd to be 0< Number < 10? How would otherwise the split in A2, B2 look if C1 >99?
???
A1 and B1 =<9, so if A1=9, B1=9 then C1 = 18 then A2=1and B2=8 then C2=9
hi Lupp1 I just got it, thanks
Concerning the recent comment by @Kevexcel on the answer by @robleyd I got another hunch:
The contents of A1, A2 might exemplify the exactly two digits of a number in decimal representation, and the actual question was about how to gt the (exactly again!) 2 digits of the sum obtained from =A1+A2.
This would be achieved by =LEF(C1;1) in A2 and =RIGHT(C1;1) in B2.
To get the digit-sum of second order then in C2 the formula there should read =VALUE(A2)+VALUE(B2)
However, this approach is by far too specialised. It will deliver nonsense (e.g.) if the digit-sum of first order already is a one-digit-number. It will not be applicable if the original number (or an intermediate digit-sum) has more than 2 digits.
See this attachment.
See also this thread in a different forum.