lol this might b a dumb question

Don’t expect it!! Baby will come in their own time! Baby can come on their own at full term 37+weeks and mines was born at 37weeks so you could go Into labor now! Or 42weeks! I mean 42 weeks because I also gave birth at 42weeks

By your math above:
38+1
+
1+6
=
40+0 (40w0d)

but obviously the real world answer here is that baby will arrive whenever the baby damn well pleases!