explain why XXXX , VX , IC , XVV are not used?

Hi!

Here is the answer to your question.

**The symbols I, X, C, M can be repeated 3 times at any given time. The symbols V, L, D can be used only once at any one instance.**

Consider XXXX and XVV,

Here X is used 4 times where as V is used twice in XXXX and XVV respectively.

Thus, XXXX and XVV are not used.

**The symbol I can be added to or subtracted from the symbol V and X only.**

Consider VX and IC,

Here V and I are subtracted from X and C respectively. But V cannot be subtracted from X and I cannot be subtracted from C.

Thus, VX and IC are not used.

Cheers!

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