The most difficult maths riddlesMathematics quiz
Which of the following Roman numerals stands for 4?
Both IV and IIII
None of the above
Both notations are correct and historically Roman numerals were often written less consistently than today. The notation 'IIII' is often seen on clock faces. The reason for that may be practical, to avoid confusing the IV and VI when the clock is held upside down (although other theories also exist).