History of Fractions
Did you know that fractions as we use them today didn't exist in
Europe until the 17th century? In fact, at first, fractions weren't
even thought of as numbers in their own right at all, just a way of
comparing whole numbers with each other. Who first used fractions?
Were they always written in the same way? How did fractions reach
us here? These are the sorts of questions which we are going to
answer for you. Read on ...
The history of fractions began with human observations of nature. The divisions of the day, the month, the seasons and the patterns in nature. The use of fractions increased as growing societies needed ways to measure goods and merchandise. Often the mathematicians interest in studying and predicting planetary movements lead to mathematical progress.
Numbers representing parts of a whole are called rational numbers or fractions, though the two are differentiated using the concept of negative numbers. Fractions can be expressed as the quotients of two Natural numbers. (a and b).
The word fraction actually comes from the Latin "fractio" which means to break. To understand how fractions have developed into the form we recognise, we'll have to step back even further in time to discover what the first number systems were like.
From as early as 1800 BC, the Egyptians were writing fractions. Their number system was a base10 idea (a little bit like ours
now) so they had separate symbols for 1 , 10 , 100 , 1000 , 10000 , 100000 and 1000000 . The ancient Egyptian writing
system was all in pictures which were called hieroglyphs and in the
same way, they had pictures for the numbers:
Here is an example of how the numbers were made up:
Could you write down3581 in hieroglyphics?
The Egyptians wrote all their fractions using what we call unit fractions. A unit fraction has1 as its numerator (top number).
They put a mouth picture (which meant part) above a number to make
it into a unit fraction. For example:
They expressed other fractions as the sum of unit fractions, but they weren't allowed to repeat a unit fraction in this addition. For example this is fine:
34=12+14
But this is not:
27=17+17
The huge disadvantage of the Egyptian system for representing fractions is that it is very difficult to do any calculations. To try to overcome this, the Egyptians made lots of tables so they could look up answers to problems.
In Ancient Rome, fractions were only written using words to describe part of the whole. They were based on the unit of weight which was called the as. One "as" was made up of 12 uncia so fractions were centred on twelfths. For example:
112 was called uncia
612 was called semis
124 was called semuncia
1144 was called scripulum
As with the Egyptian system, the words made it very difficult to do calculations.
The Babylonians were the first people to come up with a more sensible way of representing fractions. In fact they did this before the Romans' methods but there was no contact between the two civilisations. The Babylonians lived in the country we now call Iraq in the Middle East. Their number system was organised around the number60 , so we say it is base 60 . In other words they
grouped numbers into 60 s, whereas we group into 10 s. (We still
use base 60 in our measurement of time and angles.) However, they
also grouped into 10 s and so only had two symbols, one for a unit
and one for a 10 :
Here are the numbers from1 to 20 .
Can you see the symbol for1 ?
What about the symbol for10 ?
How would you write47 ?
The Babylonians simply extended their numbers to include fractions in sixtieths, as we do for tenths, hundredths etc. However, they didn't have a zero or anything like a decimal point. This made reading numbers very confusing as they could be interpreted in different ways. Here's an example:
From the table above, you can see that the two numbers are 12
and 15 . Now, this is where it becomes confusing. This could mean
several different things:
So, although the Babylonians had a very sophisticated way of writing fractions, it did have its drawbacks. Around 311BC they devised a zero so this made things easier, but without a decimal point, it was still difficult to distinguish fractions from whole numbers. We are now reaching the end of our journey through the history of fractions! The format we know today comes directly from the work of the Indian civilisation. The success of their way of writing fractions is due to the number system they created which has three main ideas:
i) Each figure has a symbol which isn't like the value it represents
ii) The value of the figure depends on the position of it within the entire number
iii) A zero is needed to mean nothing and also to fill the place of units that are missing
By about 500AD, the Indians had developed a system from a way of writing called brahmi, which had nine symbols and a zero. Again, this was devised a long time before some of the other ways of counting we have already discussed. However it was only through the trading of the Arabs that these Indian numerals were spread to Arabia where they were used in the same form. The chart below shows how these brahmi symbols became the numbers we know today:
In India fractions were written very much like we do now, with one
number (the numerator) above another (the denominator), but without
a line. For example:
Adapted from
The history of fractions began with human observations of nature. The divisions of the day, the month, the seasons and the patterns in nature. The use of fractions increased as growing societies needed ways to measure goods and merchandise. Often the mathematicians interest in studying and predicting planetary movements lead to mathematical progress.
Numbers representing parts of a whole are called rational numbers or fractions, though the two are differentiated using the concept of negative numbers. Fractions can be expressed as the quotients of two Natural numbers. (a and b).
The word fraction actually comes from the Latin "fractio" which means to break. To understand how fractions have developed into the form we recognise, we'll have to step back even further in time to discover what the first number systems were like.
From as early as 1800 BC, the Egyptians were writing fractions. Their number system was a base
Could you write down
The Egyptians wrote all their fractions using what we call unit fractions. A unit fraction has
Here is one fifth.
Can you work out how to write one sixteenth?
They expressed other fractions as the sum of unit fractions, but they weren't allowed to repeat a unit fraction in this addition. For example this is fine:
But this is not:
The huge disadvantage of the Egyptian system for representing fractions is that it is very difficult to do any calculations. To try to overcome this, the Egyptians made lots of tables so they could look up answers to problems.
In Ancient Rome, fractions were only written using words to describe part of the whole. They were based on the unit of weight which was called the as. One "as" was made up of 12 uncia so fractions were centred on twelfths. For example:
As with the Egyptian system, the words made it very difficult to do calculations.
The Babylonians were the first people to come up with a more sensible way of representing fractions. In fact they did this before the Romans' methods but there was no contact between the two civilisations. The Babylonians lived in the country we now call Iraq in the Middle East. Their number system was organised around the number
Here are the numbers from
Can you see the symbol for
What about the symbol for
How would you write
The Babylonians simply extended their numbers to include fractions in sixtieths, as we do for tenths, hundredths etc. However, they didn't have a zero or anything like a decimal point. This made reading numbers very confusing as they could be interpreted in different ways. Here's an example:
x60 | Units | Sixtieths | Number |
So, although the Babylonians had a very sophisticated way of writing fractions, it did have its drawbacks. Around 311BC they devised a zero so this made things easier, but without a decimal point, it was still difficult to distinguish fractions from whole numbers. We are now reaching the end of our journey through the history of fractions! The format we know today comes directly from the work of the Indian civilisation. The success of their way of writing fractions is due to the number system they created which has three main ideas:
i) Each figure has a symbol which isn't like the value it represents
ii) The value of the figure depends on the position of it within the entire number
iii) A zero is needed to mean nothing and also to fill the place of units that are missing
By about 500AD, the Indians had developed a system from a way of writing called brahmi, which had nine symbols and a zero. Again, this was devised a long time before some of the other ways of counting we have already discussed. However it was only through the trading of the Arabs that these Indian numerals were spread to Arabia where they were used in the same form. The chart below shows how these brahmi symbols became the numbers we know today:
It was the Arabs who added the line (sometimes drawn
horizontally, sometimes on a slant) which we now use to separate
the numerator and denominator:
34
So here we have the fraction as we now recognise it. It is amazing
to think how much thought has gone into the way we write it down,
isn't it? Perhaps next time you use fractions, you'll remember
this.Adapted from
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