Counting Roman Numerals Up to 1000 Mathematics Primary 4 First Term Lesson Notes Week 5

Grade: Primary 4

Subject: Mathematics

Topic: Roman Numerals

Duration: 45 minutes

Learning Objectives: By the end of this lesson, students should be able to:

1. Understand the basic concept of Roman numerals.
2. Identify Roman numerals from I to X and their corresponding values.
3. Convert Arabic (standard) numbers to Roman numerals.
4. Convert Roman numerals to Arabic numbers.

Embedded Core Skills:

• Numeracy skills.
• Critical thinking.
• Problem-solving.
• Basic research skills.

Learning Materials:

1. Whiteboard and markers.
2. Roman numeral chart (I to X) as visual aid.
3. Flashcards with Arabic numbers and corresponding Roman numerals.
4. Previous lesson notes on “Ordering of Whole Numbers.”

Reference Materials:

• Roman numeral reference chart.
• Examples of Roman numerals in books or online resources (for teacher’s reference).

Previous Lesson (Ordering of Whole Numbers):

• Begin by briefly reviewing the previous lesson on “Ordering of Whole Numbers.” Ask students to recall how we arrange numbers from smallest to largest.

Set Induction (5 minutes):

• Begin the lesson by asking students if they have ever seen Roman numerals before (e.g., in movie credits or on clock faces). Encourage them to share their observations.

Content (15 minutes): Understanding Roman Numerals:

• Explain that Roman numerals are a different way of writing numbers that were used by ancient Romans.
• Show a chart with Roman numerals from I to X and their corresponding values. For example:
  • I = 1
  • II = 2
  • III = 3
  • IV = 4
  • V = 5
  • VI = 6
  • VII = 7
  • VIII = 8
  • IX = 9
  • X = 10

Converting Arabic to Roman Numerals:

• Demonstrate how to convert Arabic (standard) numbers to Roman numerals. Use examples like:
  • 1 to I
  • 3 to III
  • 7 to VII
  • 10 to X

🌟 Introduction to Roman Numerals:

Roman numerals are special symbols that the ancient Romans used to write numbers. Instead of using the numbers we use today (like 1, 2, 3, 4, and so on), the Romans used letters to represent numbers.

Here are the basic Roman numerals and what they mean:

• I = 1
• V = 5
• X = 10
• L = 50
• C = 100
• D = 500
• M = 1000

🌟 Examples of Roman Numerals:

1. I: This is the simplest Roman numeral, and it represents the number 1. It looks like a straight line.
2. V: The Roman numeral V stands for 5. It looks like a “V,” which can remind us of the number 5.
3. X: When you see an X, you’re looking at the Roman numeral for 10. It’s like two V’s put together, which makes sense because 2 fives make 10.
4. L: L represents 50. Think of it as a fancy L for fifty.
5. C: C is 100. Imagine it as a C turned into a 100 by adding a little curve on top.
6. D: D stands for 500. You can think of it as a D with an extra line to make it 500.
7. M: M is the biggest Roman numeral we’re talking about today. It means 1000. It’s like two Ds stacked together, making it look like 1000.

🌟 More Examples:

• III is 3 because it’s three I’s (1 + 1 + 1).
• IV is 4 because it’s one less than 5 (5 – 1).
• IX is 9 because it’s one less than 10 (10 – 1).
• XX is 20 because it’s two X’s (10 + 10).
• XL is 40 because it’s 10 less than 50 (50 – 10).
• XC is 90 because it’s 10 less than 100 (100 – 10).

🌟 Summary:

So, in Roman numerals, we use letters to show numbers. It’s like a secret code the ancient Romans used long ago. Remember, I is 1, V is 5, X is 10, L is 50, C is 100, D is 500, and M is 1000. With these symbols, you can write many different numbers in Roman numerals!

Practice writing some Roman numerals and see how many numbers you can make using these special symbols. 🧡📜

 

Roman numerals from I to X along with their corresponding values:

1. I represents the number 1.
2. II represents the number 2 (I + I).
3. III represents the number 3 (I + I + I).
4. IV represents the number 4 (5 – 1).
5. V represents the number 5.
6. VI represents the number 6 (5 + 1).
7. VII represents the number 7 (5 + 1 + 1).
8. VIII represents the number 8 (5 + 1 + 1 + 1).
9. IX represents the number 9 (10 – 1).
10. X represents the number 10.

[mediator_tech]

Roman Numeral	Value
I	1
II	2
III	3
IV	4
V	5
VI	6
VII	7
VIII	8
IX	9
X	10
XI	11
XII	12
XIII	13
XIV	14
XV	15
XVI	16
XVII	17
XVIII	18
XIX	19
XX	20
XXI	21
XXII	22
XXIII	23
XXIV	24
XXV	25
XXVI	26
XXVII	27
XXVIII	28
XXIX	29
XXX	30
XL	40
L	50
LX	60
LXX	70
LXXX	80
XC	90
C	100
CC	200
CCC	300
CD	400
D	500
DC	600
DCC	700
DCCC	800
CM	900
M	1000

These Roman numerals and their values were used by the ancient Romans for various purposes, including counting, recording dates, and in architectural designs

[mediator_tech]

some examples of converting Arabic (standard) numbers to Roman numerals:

1. 5 in Roman Numerals: V
   • The Arabic number 5 is represented as V in Roman numerals.
2. 12 in Roman Numerals: XII
   • To write 12 in Roman numerals, you use X (10) and add II (2) after it.
3. 23 in Roman Numerals: XXIII
   • To write 23 in Roman numerals, you use XX (20) and add III (3) after it.
4. 39 in Roman Numerals: XXXIX
   • For 39, you use XXX (30) and add IX (9) after it.
5. 50 in Roman Numerals: L
   • The Roman numeral for 50 is simply L.
6. 88 in Roman Numerals: LXXXVIII
   • To represent 88, you use LXXX (80) and add VIII (8) after it.
7. 99 in Roman Numerals: XCIX
   • For 99, you use XC (90) and add IX (9) after it.
8. 100 in Roman Numerals: C
   • The Roman numeral for 100 is C.
9. 356 in Roman Numerals: CCCLVI
   • To write 356, you use CCC (300), add L (50), and then VI (6).
10. 500 in Roman Numerals: D
    • The Roman numeral for 500 is D.

These examples show how you can convert standard Arabic numbers into Roman numerals. It’s like solving a puzzle!

 

Evaluation

1. To write 7 in Roman numerals, you use ___.
a) VII
b) IV
c) IX
d) II

2. What is the Roman numeral for 20?
a) XX
b) X
c) XXX
d) L

3. If you want to represent 42 in Roman numerals, you write ___.
a) XLII
b) XII
c) XXII
d) LII

4. The Roman numeral for 100 is ___.
a) X
b) C
c) D
d) M

5. To write 16 in Roman numerals, you use ___.
a) XVI
b) IVI
c) XIX
d) XII

6. What Roman numeral represents the number 9?
a) VII
b) X
c) IX
d) XI

7. If you see the Roman numeral “LX,” it stands for ___.
a) 60
b) 10
c) 100
d) 50

8. How do you write 75 in Roman numerals?
a) V
b) L
c) XV
d) LXXV

9. What is the Roman numeral for 400?
a) CD
b) D
c) CCC
d) CC

10. If you want to represent 88 in Roman numerals, you write ___.
a) LXVIII
b) LXXXVIII
c) XVIII
d) VIII

11. The Roman numeral for 500 is ___.
a) C
b) L
c) D
d) M

12. To write 99 in Roman numerals, you use ___.
a) CIX
b) XCIX
c) LIX
d) IX

13. What Roman numeral stands for the number 10?
a) X
b) IV
c) IX
d) V

14. The Roman numeral for 3 is ___.
a) II
b) IV
c) V
d) III

15. How do you write 600 in Roman numerals?
a) D
b) CD
c) CCC
d) DC

🌟 Introduction to Converting Roman Numerals:

Converting Roman numerals to Arabic numbers can be fun and interesting. Roman numerals are like a secret code, and we’ll learn how to decode them!

🌟 The Rules:

To convert Roman numerals to Arabic numbers, you need to follow some simple rules:

1. Start from Left to Right: Always start from the left side of the Roman numeral and move to the right.

2. Add Values: Add the values of the Roman numerals together.

3. Pay Attention to Special Cases: Watch out for special cases where you subtract instead of adding.

🌟 Examples:

Let’s convert some Roman numerals into Arabic numbers together!

Example 1: Roman Numeral – VII

• Start with the leftmost letter, which is V (5).
• Now, move to the right to find the next letter, which is I (1).
• Add them together: V (5) + I (1) = 6.
• So, VII in Roman numerals is 6 in Arabic numbers.

Example 2: Roman Numeral – XIV

• Begin with X (10) on the left.
• Then, move to the right and find I (1).
• Add them together: X (10) + I (1) = 11.
• But, there’s a special case: IV means subtract 1 from 5, so we subtract 1.
• So, XIV in Roman numerals is 14 in Arabic numbers.

Example 3: Roman Numeral – XL

• Start with X (10) on the left.
• Then, move to the right and find L (50).
• But, there’s a special case: XL means subtract 10 from 50, so we subtract 10.
• So, XL in Roman numerals is 40 in Arabic numbers.

🌟 Practice:

Now, you can try converting some Roman numerals to Arabic numbers on your own. Remember the rules: start from the left, add values together, and watch out for special cases.

Converting Roman numerals to Arabic numbers is like solving a puzzle, and it can be a lot of fun! 😊🔢

[mediator_tech]

Evaluation

1. Convert XVII to Arabic numbers: ___.
a) 15
b) 16
c) 17
d) 18

2. What is the Arabic equivalent of XXVIII?
a) 28
b) 29
c) 27
d) 30

3. Convert XIV to Arabic numbers: ___.
a) 12
b) 14
c) 16
d) 18

4. What is the Arabic value of XLII?
a) 41
b) 42
c) 43
d) 44

5. Change XXXIII to Arabic numbers: ___.
a) 30
b) 32
c) 33
d) 34

6. What does the Roman numeral L represent in Arabic numbers?
a) 40
b) 50
c) 60
d) 70

7. Convert CXXV to Arabic numbers: ___.
a) 115
b) 125
c) 135
d) 145

8. What is the Arabic equivalent of LXXXIX?
a) 78
b) 88
c) 89
d) 99

9. If you see the Roman numeral MM, what is the Arabic value?
a) 1000
b) 2000
c) 3000
d) 4000

10. Change XLVII to Arabic numbers: ___.
a) 47
b) 48
c) 49
d) 50

11. What is the Arabic number for XCIV?
a) 94
b) 95
c) 96
d) 97

12. Convert CCCXII to Arabic numbers: ___.
a) 311
b) 312
c) 313
d) 314

13. What does the Roman numeral D represent in Arabic numbers?
a) 400
b) 500
c) 600
d) 700

14. If you have the Roman numeral CM, what is its Arabic value?
a) 900
b) 1000
c) 800
d) 700

15. Change MCMXC to Arabic numbers: ___.
a) 1990
b) 1980
c) 2000
d) 1900

 

Presentation (10 minutes):

• Use flashcards with Arabic numbers and corresponding Roman numerals for interactive learning.
• Engage students in identifying the Roman numerals and their values on the flashcards.

Teacher’s Activities (5 minutes):

• Summarize the main points of the lesson.
• Encourage students to ask questions or share their thoughts.

Learners’ Activities (5 minutes):

• Allow students to practice converting Arabic numbers to Roman numerals and vice versa with a partner.

Assessment (5 minutes):

• Distribute a worksheet with exercises for students to convert Arabic numbers to Roman numerals and vice versa.
• Collect and review the worksheets to assess students’ understanding.

Conclusion (5 minutes):

• Recap the key concepts of Roman numerals.
• Ask students to share any interesting facts they learned about Roman numerals.

Homework:

• Assign homework that involves students converting Arabic numbers to Roman numerals and vice versa using a worksheet.