adding every other column

[gma]

i need a formula in cell A1 to total cell C1 and everyother column after that
i.e. E1,G1 ect
i need a formula in cell B1 to total cell D1 and everyother column after
that i.e. F1,H1 ect
how do i do that?

 

[ryguy7272]

I'm on a new computer now; Office not installed yet so I can't try this and
show you how it works, but I assume you can see the samples here and replace
the 'Row' with 'Column':
http://www.mrexcel.com/td0066.html

Or, look here:
http://www.mcgimpsey.com/excel/formulae/sumeverynth.html

 

[FSt1]

hi
you are wanting to sum everyother column ie even numberd column and odd
numbered columns. your columns may have letters but excel can display them as
numbered columns. A,C,E,G etc are odd. B,D,F,H are even.
tools>options>general tab>check R1C1 reference style to see what i mean.
to sum odd columns, in A1 use this fomula.....
=SUMPRODUCT((MOD(COLUMN(C1:M1),2)=1)*(C1:M1))
adjust ranges to suit your data.
to sum even columns, in B1 use this formula.....
=SUMPRODUCT((MOD(COLUMN(D1:M1),2)=0)*(D1:M1))

regards
FSt1

 

[gma]

leave it up to me to screw up the question....the formula you gave me works
great but instead of me needing to add every other column, i need the formula
to add every third column. how do i do that?

 

[Rick Rothstein]

Try this...

=SUMPRODUCT((MOD(COLUMN(C1:M1),3)=0)*(C1:M1))

Adjust the M1's to whatever column is your maximum anticipated one to be
used.

 

[T. Valko]

To sum every 3rd cell starting from cell C1: (C1,F1,I1,L1,etc.)

=SUMPRODUCT(--(MOD(COLUMN(C1:T1)-COLUMN(C1),3)=0),C1:T1)

To sum every 3rd cell starting from cell D1: (D1,G1,J1,M1,etc.)

=SUMPRODUCT(--(MOD(COLUMN(D1:T1)-COLUMN(D1),3)=0),D1:T1)

In each formula adjust for the correct end of range T1.

Caveat: inserting new columns *within* the referenced range will cause the
formulas to calculate the incorrect cell interval.

 

[gma]

super...thanks!!!!

To sum every 3rd cell starting from cell C1: (C1,F1,I1,L1,etc.)

=SUMPRODUCT(--(MOD(COLUMN(C1:T1)-COLUMN(C1),3)=0),C1:T1)

To sum every 3rd cell starting from cell D1: (D1,G1,J1,M1,etc.)

=SUMPRODUCT(--(MOD(COLUMN(D1:T1)-COLUMN(D1),3)=0),D1:T1)

In each formula adjust for the correct end of range T1.

Caveat: inserting new columns *within* the referenced range will cause the
formulas to calculate the incorrect cell interval.

--
Biff
Microsoft Excel MVP





.

 

[T. Valko]

You're welcome. Thanks for the feedback!