Sum across columns

i have a data table laid out in the following manner;

ColA ColB ColC ColD ColE ColF
Product Desc Ohio Georgia NewYork Indiana
X A 5 4 3 4
Y B 3 2 5 1
Z C 6 3 6 2


I want to create a sumtotal in ColG from ColC,ColD,ColE and ColF but all vaules in ColC have to be multiplied by a factor of 2, colD by 3, colE by 1.5 and colF by 3.5.

This list is dynamic and can grow by rows and columns. The factor by which a state is multiplied will always be the same for the state. Essentially, the factor for all states will be coded and will never change.

How can i loop through all the col's with state names, evaluate the name, apply the factor and sum the result for every state in colG.

this what i use to just sum the data by product

Dim cv As Range
Dim lastcol As Long
lastcol = Range("A4").End(xlToRight).Column

For Each cv In Range(Sheet2.Range("A4").End(xlToRight).Offset(1, 1), Cells(Rows.Count, "A").End(xlUp).Offset(0, lastcol))

rn = cv.Row

cv.Value = Application.Sum(Range(cv.Offset(0, -1), "C" & (rn)))

Next cv

Sheet2.Range("A4").End(xlToRight).Offset(0, 1).Value = "Ttl Trx Count"

But i also need to need to add the factors based on the state name and sum all that as well. Any ideas on how to get there will be helpfull.

Thanks

Does this work? See attachment.

Sub x()

Dim r As Long, c As Long

c = Cells(1, Columns.Count).End(xlToLeft).Column
For r = 3 To Cells(Rows.Count, 1).End(xlUp).Row
    Cells(r, c + 1) = WorksheetFunction.SumProduct _
        (Range(Cells(1, 3), Cells(1, c)), Range(Cells(r, 3), Cells(r, c)))
Next r

End Sub

Thank you very much. Both solutions will work, but in this particular case i can't reveal formulas in the sheet and it has to be done in code. I adapted StephenR's solution with slight modifications to suit how my sheet is laid out.

Thanks again