Transcript Roman Numerals - Hampton School

Roman Numerals
Instead of using digits, Romans used letters to show
numbers. You may have seen the before.
This lesson will teach you how to use Roman numerals.
Read each slide carefully before going on!
Roman
English
Roman
English
Roman
English
I
1
XI
11
XXX
30
II
2
XII
12
XL
40
III
3
XIII
13
L
50
IV
4
XIV
14
LX
60
V
5
XV
15
LXX
70
VI
6
XVI
16
LXXX
80
VII
7
XVII
17
XC
90
VIII
8
XVIII
18
C
100
IX
9
IXX
19
D
500
X
10
XX
20
M
1000
Roman Numerals
The 4 rules of Roman numerals:
1) Small numbers before large
numbers subtract: IV = 4
2) Smaller or equal numbers after
large numbers add: VI = 6
3) You never add more than three
of the same number to a larger
number: 9 = IX, NOT VIIII
4) You never subtract more than
one of the same number from a
larger number: 8 = VIII, NOT IIX
Roman
English
I
1
V
5
X
10
L
50
C
100
D
500
M
1000
Roman Numerals
Roman
English
I
1
V
5
X
10
L
50
C
100
D
500
M
1000
To create big numbers, go from left
to right, doing the last two digits
together:
678:
600: DC
78:
LXXVIII
678: DCLXXVIII
(500+100)
(50+20+8)
2419:
2000:
400:
19:
2419:
(1000+1000)
(500-100)
(20-1)
MM
CD
IXX
MMCDIXX
Roman Numerals
Roman
English
I
1
V
5
X
10
L
50
C
100
D
500
M
1000
Your turn! Turn the following
English numbers into Roman
numerals in your rough books:
1) 8
2) 28
3) 45
4) 67
5) 82
6) 136
7) 349
8) 698
9) 1,789
10) 2012
Answers are on the next slide.
Roman Numerals
Roman
English
I
1
V
5
X
10
L
50
C
100
D
500
M
1000
How did you do?
1) VIII
2) XXVIII
3) XLV
4) LXVII
5) LXXXII
6) CXXXVI
7) CCCIL
8) DCXCVIII
9) MDCCLXXXIX
10) MMXII
Roman Numerals
Optime! You have now taken your
first steps towards being a Roman
mathematician!
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another lesson.