[Young Werther]

Not! 911 is CMXI. IX is nine and XI is eleven. but IXXI is nonsense in Roman Numeral codification.

I - One

V- Five

X - Ten

L - Fifty

C - Hundred

D - Five Hundred

M - Thousand.

IX - XI would be 9-11.

[digger48]

note post 24, please