Roman Numerals Students will convert Arabic numerals to Roman numerals and vice versa Students will write numbers using the Roman numeral system

When do you use Roman numerals?

Roman Numerals up to 3999 Arabic RomanIVXLCDM Mneumonic for Roman Numerals

Roman Numerals 4000 and above

Combine symbols to make Roman numerals Read left to right If the small numeral comes after a big numeral, add it (add as much as three) –VIII V + I + I + I = –XV X + V = –LX L + X = –MDCCCLXXXVIII = 1888 Arabic RomanIVXLCDM

Practice adding Roman numerals *Break up Roman and Arabic numerals by places = MMLXI MM--LXI= 3253 = DCXXXV = 86 = Arabic RomanMDC LXV I

Combine symbols to make Roman numerals Arabic RomanIVXLCDM Read left to right If the small numeral comes before a big numeral, subtract it (subtract only one symbol at a time, one place value away) –IX -I + X = –XIV X + IV = 10 + (-1 + 5) –CD -C + D = –MCMXCIX M CM XC IX ( ) + ( ) + ( ) = 1999

Combine symbols to make Roman numerals Arabic RomanIVXLCDM Quick overview of Roman numerals which subtract the symbol on the left from the symbol on the right: IV( = 4)IX( = 9) XL ( = 40)XC( = 90) CD ( = 400)CM( = 900) VVL ≠ XL (simplify!) LC ≠ L (simplify!) IIX ≠ VIII (you can only subtract one symbol at a time) IC ≠ XCIX (you can only subtract from one place value away)

Practice subtracting Roman numerals *Break up Roman and Arabic numerals by places = MMXLI MM--XLI= 3493 = MCMXL = 89 = Arabic RomanMDC LXV I

Combine symbols to make Roman numerals It was easier to carve numerals like quattuor and novem as IV and IX instead of IIII and VIIII. VIIII vs. VIII can be hard to distinguish. What is this number? VIIIII

XI-XX XI XII XIII XIV XV XVI XVII XVIII XIX XX undecim duodecim tredecim quattuordecim quindecim sēdecim septendecim duodēvīgintī undēvīgintī vīgintī

XXI-XXX? XXI__________vīgintī ūnus/-a/-um XXII__________vīgintī duo/-ae/-o XXIII__________vīgintī trēs/tria XXIV__________vīgintī quattuor XXV__________vīgintī quinque XXVI__________vīgintī sex XXVII__________vīgintī septem XXVIII__________vīgintī octō / duodētrīgintī XXIX__________vīgintī novem / undē trīgintī XXX__________trīgintā

L, C, D, M Lquīnquāgintā Ccentum Dquīngentī/-ae/-a Mmille MMduo mīlia

XL - MM XL L LX LXX LXXX XC C CI D M MM MMMCMXCIX quadrāgintā quīnquāgintā sexāgintā septuāgintā octōgintā nōnāgintā centum centum ūnus quīngentī/-ae/-a mille duo mīlia trēs mīlia nongentī nōnāgintā et novem

MMMCMXCIX trēs mīlia nongentī nōnāgintā et novem MMMCMXCIX MMM = CM = 1000 – 100 XC = 100 – 10 IX = 10 –

Roman Numeral Practice MMXIV__________2014 MCMXCIX__________1999 DCCLIII__________753 BCE XCVII__________97 MCMLXXXIV__________1984 MCDXCII__________1492

Roman Numeral Practice CDLIII __________ CMXCVI__________ MMXI __________ CIX__________ MCMXLIV__________ MMMCDXCI__________