To average a non-contiguous range in Excel, you can use the SUMPRODUCT function. This function multiplies ranges or arrays together and returns the sum of those products.

For example, to average cells A1:A5 and C1:C5, you can use the following formula:

=SUMPRODUCT(A1:A5,C1:C5)/SUM(A1:A5)

You can also use the AVERAGE function to average a non-contiguous range. This function simply calculates the arithmetic mean of a given set of values.

For example, to average cells A1:A5 and C1:C5, you can use the following formula:

=AVERAGE(A1:A5,C1:C5)