2. EQ: How do you read and write Roman Numerals?

3. Where do you see Roman Numerals? Super Bowl & Olympics Movies Clocks Outlines Books Names (Henry VIII)

4. Roman numerals are part of the ancient Roman number system that remains in use today. The history of Roman numerals dates back to 1st millennium BC when they were used to record numbers in stone, art and coins. Roman numerals add a classic style that Arabic numerals cannot. Arabic (decimal) numbers ( 0 to 9 ) were introduced into Europe about 900 AD and were adopted quickly for their convenience and mathematical ease of use.

5. Let’s Learn the Roman Numerals… I = one V = five X = ten L = fifty C = 100 D = 500 M = 1,000 There isn’t a symbol for zero.

6. The Rules for Writing Roman Numerals The letters should be arranged from largest to smallest. –1510 is written MDX, largest to smallest Only powers of ten can be repeated. Don’t repeat a letter more than three times in a row. –100 is written C, not XXXXXXXXXX (too many repeats)

7. Rules Continued Numbers can be written using subtraction. If you place any smaller number in front of a larger number it symbolizes subtraction. For example, IV=4. It is really saying that 5 - 1 equals 4. –Only powers for ten (I, X, C) can be subtracted. –I can only be subtracted from V or X

8. Practice 515 = ? 39 = ? 1005 = ? 32 = ? 9= ?

9. Answers 515 = DXV 39 = XXXIX 1005 = MV 32 = XXXII 9= IX

10. Adding Roman Numerals Write down the two numbers you are adding right next to each other Rearrange the letters so they start with the largest and end with the smallest. Then start combining similar letters. Check you answer by adding the Arabic numbers.

11. Now Let’s Try Adding Problem 1.23 + 58

12. Answer to the Adding Problem Step 1. 23 + 58 Step 2. XXIII + LVIII Step 3. XXIIILVIII Step 4. LXXVIIIIII Step 4. IIIIII = VI Step 5. LXXVVI Step 6. VV = X Step 7. LXXXI = 81 Step 8. 23 + 58 = 81 Roman NumeralNumber I1 V5 X10 L50 C100 D500 M1000

13. REALLY BIG NUMBERS! If there is a line under the Roman Numeral “V, X, L, C, D, or M” it means to add 3 zeros (multiply it by 1,000). V would mean 5,000. VIV IXLII

14. Now try these: 1. XXXVI 2. XL 3. XVII 4. DCCLVI 5. MCMLXIX

15. Click on the number that matches the Roman Numeral.

16. 1.LXIII A. 5353 B. 6363 C. 113113

17. OOPS! Try again!

18. You are correct! LXIII = 50+10+3 = 63 L=50; X=10; III=3 Remember:

19. 2.DCXXIV A. 624624 B. 16241624 C. 55245524

20. OOPS! Try again!

21. You are correct! DCXXIV= 500+100+20+4= 624

22. 3. CCL A. 150150 B. 250250 C. 550550

23. OOPS! Try again!

24. You are correct! CCL = 100+100+50=250