The following worksheet is an example:
A1: 10.5 B1: 2 C1: =PRODUCT(A1,B1)
A2: 10.5 B2: 0 C2: =PRODUCT(A2,B2)
A3: B3: C3:
A4: 10.5 B4: C4: =PRODUCT(A4,B4)
The formulas in C1, C2, and C4 return 21, 0, and 10.5, respectively.
The blank cell in B4 is computed as the value 1 so that the PRODUCT
function will not return a value of 0 when used to sum a range of
cells that includes blank cells.
You can force the PRODUCT function to evaluate blank cells as zero by
adding
*1 to each argument within the function. For
example, the formula
=PRODUCT(A4*1,B4*1)
will return a value of zero, rather than 10.5 as shown above.