I have a column with numbers A (as text, I want to keep initial zeros):

05...
07...
08...
12...
41...

In another column B I want a letter that depends on the initial numbers
in the A-column. If the initial number is 0 I want an "F" in B, if it is
07 I want "M" in B and in all other cases I want an "U" in B:

F 05...
M 07...
F 08...
U 12...
U 41...

I created a formula for this purpose:

=IF(
FIND("07";LEFT(B3;2);1);
"M";
IF(FIND("0";LEFT(B3;1);1);"F";"U"))

The problem is that it only works for the M-cases. All other cases
return a value-error. However, if I break out line 4 in the formula it
works as expected. I am puzzled.

Any ideas why it doesn't work and how I can fix it?

This is in MacExcel but that shouldn't matter, should it?

--
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