I would like to add the number displayed in every 15th cell in the B
column (starting with B20) and display those results in B5. Instead of
using
=(B20+B35+B50...)
is there a quicker formula I can use?


ALSO:

Is there a workday formula I can use to put the first workday of any
given month in a target cell, and then every 15th cell in the same row,
put the following day?

So: A1= 5/2/05
A16= 5/3/05
and so on...

Thanks guys!!!!!!!!!!!!!