igsce maths directed numbers basic 2

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directed numbers
basics
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in this lesson
we look at the history of these numbers
we look at the ancient Chinese rod numerals
we look at the other people who used directed
numbers
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ancient Chinese rod numerals
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Chinese rod numerals
positive numbers in red
vertical rods
horizontal rods
1
7
9
2
4
5
6
8
3
negative numbers in black
vertical rods
horizontal rods
-5
-6
-7
-8
-9
-1
-2
-3
-4
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examples
some numbers in Chinese rod numerals
blank for zero

1.
203

blank for zero
2.
-20
3.

56
-741
4.

5.
blank for zero
7905

blank for zero
6.

-2067
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exercises
write down the numbers below using Chinese rod
numerals
1.
104
2.
-30
3.
356
-861
4.
5.
7509
6.
-1902
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answers
the numbers below using Chinese rod numerals

1.
104

2.
-30
3.
356

-861
4.

5.
7509

6.

-1902
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other people who used the directed numbers in the
past
source http//www.wikipedia.com
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(No Transcript)
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summary
we looked at the history of these numbers
we saw the ancient Chinese rod numerals
we saw other people who used directed numbers
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