Rab Swinney wrote:
How do I remove a decimal place to return the following
0900.000 to 0900000
I know I can use the left and right function and & them, the problem is the
first 4 digits can be 5 or 6 digits

If your original number (0900.000) is text, the following might do the
job for you:

=substitute(A1,".","")