A1 contains:

8101940

=======================

B1 contains this formula:

=TEXT(A2,"000000000")

=======================

C1 contains this formula:

=MID(B2,1,1)*1+MID(B2,2,1)*3+MID(B2,3,1)*7+MID(B2, 4,1)*9+MID(B2,5,1)*1+MID(B2,6,1)*3+MID(B2,7,1)*7+M ID(B2,8,1)*9+MID(B2,9,1)*1

======================

D1 contains this formula:

=RIGHT(C2,1)

======================

E1 contains this formula:

=B2&"-"&D2

which displays:

008101940-7

=============================================

How can I combine the 4 formulas so B2 contains the combination of the
4 formulas and diplays:

008101940-7