Multiple choice Which of the following numbers is denoted by XC? 40 60 70 90 Reveal answer Fill a bubble to check yourself D Correct answer Explanation The roman number series: MCMXCIX = M C M X C I X = 1000 + (1000 - 100) + (100 -10) + (10 - 1) = 1999 Therefore, XC = (100 - 10) = 90