I would like to format a cell to turn red and bold, when it is a number other
than the previous cell. And, I would like it to stay black when it is the
same number as the previous cell.

Ex.

A1=30 (Red & Bold)
A2=30 (Black)
A3=45 (Red & Bold)
A4=45 (Black)
A5=45 (Black)
etc.