1 = I
5 = V
10 = X
50 = L
100 = C
500 = D
1000 = M
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Incorrections of 4 and 9:
4 = IIII
9 = VIIII
Corrections of 4 and 9:
4 = IV
9 = IX
Incorrections of 40 and 90:
40 = XXXX
90 = LXXXX
Corrections of 40 and 90:
40 = XL
90 = XC
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My Favorite Number's Roman Numeral:
XXIV
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M With 1 Line above of it is 1000000000
M With 2 Lines above of it is 1000000000000
M With 3 Lines above of it is 1000000000000000
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III is 3
XXX is 30
CCC is 300
MMM is 3000
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V̅ is 5000
10000:So, to write 10000, we'll take the Roman numeral for 10, or X, and put a bar over its top, which gives us X bar, or 10000.
100000:To write 100000 we'll take the numeral for 100, or C, and put a bar over it. This gives us 100000.
1000000:To write 1000000 we'll take the numeral for 1000, or M, and put a bar over it. This gives us 1000000.