Base 60 - Motivate

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Babylonian Maths
Numbers in base 60
• What do you think these five
numbers are?
• What do you think these five
numbers are?
20
• What do you think these five
numbers are?
20
40
• What do you think these five
numbers are?
20
40
53
• What do you think these five
numbers are?
20
40
28
53
• What do you think these five
numbers are?
20
40
28
53
49
In base 60 …
• Any number between 1 and 60
corresponds to the units in our
numbers.
• Getting to 60 in base 60 is like
getting to 10 in base 10.
• We don’t need a new symbol
when we get to 10, and the
Babylonians didn’t need a new
symbol for 60.
• What do you think these three
numbers are?
60 + 1060 + 20 120 + 10
= 70
= 80
= 130
• What do you think these two
numbers are?
2 x 60 + 13
= 133
3 x 60 + 28
= 208
Writing numbers in
base 60
• You don’t have to write base 60 numbers in
cuneiform symbols.
• Look at these base 60 numbers – can you
work out what they mean?
Base 60 0 18
Base 10
18
1 39
60 + 39 = 99
3 06
11 20
180 + 6 = 186 660 + 20 = 680
• Can you change these base 10 numbers
into base 60?
Base 10
29
69
149
299
Base 60
29
1 09
2 29
4 59
Zero
• The Babylonians didn’t have a
separate symbol for 0.
• This number would have meant
3600 + 1 = 3601
• The zero lots of 60 would have just
been a gap.
• Is this a good way of showing a zero,
do you think?
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