"Five-and-twenty" seems to be the proper order for verbalizing numbers in most languages"

I think Welsh uses both a twenty and a ten base. For twenty five:. “Pump ar hugain” (five on twenty) and “Dau ddeg pump” (two ten five). Thirty in the first of these would be “deg ar hugain” (ten on twenty) and “tri deg” (three ten) in the other.