Răspuns :
399 = CCCXCIX
400 = CD
401 = CDI
402 = CDII
403 = CDIII
404 = CDIV
405 = CDV
406 = CDVI
407 = CDVII
408 = CDVIII
409 = CDIX
410 = CDX
411 = CDXI
400 = CD
401 = CDI
402 = CDII
403 = CDIII
404 = CDIV
405 = CDV
406 = CDVI
407 = CDVII
408 = CDVIII
409 = CDIX
410 = CDX
411 = CDXI