answer must contain at least one letter x

[GW47]

an old fashioned number from the 1980 film Xanadu [4]
This is driving me mad any help would be appreciated

[Calibax]

Seen answered as XXMM
An alternative way of writing 1980 in Roman numerals
(usually MDCCCCLXXX or MCMLXXX)

[Grandma_Yiddo]

That is brilliantly thought out Calibax,I spent ages thinking about it.

[bibblebub]

It's (almost definitely) not XXMM - I suggested that last evening http://www.theanswerb...7.html#answer-7286001 when I was concentrating on something else and it's just wrong.

[factor-fiction]

There are no songs (numbers) from the soundtrack that contain an X other than the title song.
I suppose the answer could be just numbers using the Roman numerals in the word Xanadu, namely X (10) or XD (490?)
Incidentally, bibblebub, I mentioned on the previous thread that XXMM does seem to be an accepted (or at least fairly common, even if wrong) alternative MDCCCCLXXX or MCMLXXX for 1980