Chapter 4 – Fractions
Map
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1.19
Timeline
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1.19
Introduction
Can you recall a word that sounds like “fraction” and even means the same? It is a word that we use in everyday life. Like when your friend is skiing downhill, falls and … his leg? Right, the word is “to fracture.” The word “fraction” comes from the Latin word “fraction,” which means “a breaking.” It reflects the idea of breaking something into smaller parts, which is what a fraction represents.
The fractions that we use today come to us from ancient Egypt. The ancient Egyptians developed symbols that represented parts, such as halves, quarters, and thirds, as opposed to wholes, like one, three, or four. One of the reasons that the Egyptians needed fractions was that for thousands of years, there was no real money in Egypt. In ancient world, before inventing money such as coins or banknotes, people used different objects to represent the cost of things. Cacao beans, cowrie shells, whale teeth, and giant stones were among objects used as money in different cultures around the globe. Early civilizations were especially fond of metals, particularly silver and gold, which were used to trade and exchange goods and services. But the Egyptians didn’t bother with real objects for money. Instead of money, the Egyptians used a system called barter. The barter system is where people trade goods or services for other goods and services without the use of money. For example, someone may trade grain for a fur coat, or someone may trade food in exchange for help with a harvest. Bartering can be tricky because both people must agree that the trade is fair. For most of its history, ancient Egypt’s economy operated on a barter system without cash. Instead of cash, they had virtual money, believe it or not, similar to modern bitcoins! A virtual coin was called deben and everything was priced in debens. In every given time in Egypt there were known prices for almost every item imaginable, for instance, 1 cake: 1/5 deben, 1 bundle of vegetables: ½ deben, 1 shirt: 2½ deben, 1 goat: 2½ deben, 1 litre of oil: 1 deben, 1 loaf of bread: 1/10 deben, 1 slave girl: 4 deben, 1 ordinary male slave: 3 deben (yes, slaves, don’t be surprised – every civilization had slaves. Also, do you know that the word “slave” comes from an old French word for slavs the people from Eastern Europe? Back in the time, they were the majority of enslaved people.)
So the barter worked like that: you compare prices and trade. If a litre of oil costed one deben, and a loaf of bread was 1/10 of deben, 1 litre of oil could be traded fairly for 10 loaves of bread. In this same way, if one jug of beer costed a 1/3 deben and a day’s work was worth one deben, then one would fairly be paid three jugs of beer for one’s daily labour. Let’s imagine that you are an ancient Egyptian who hired workers to work in your field or build a shed for you.
You and your workers agreed that you would pay them in beer and bread (that was the usual form of payme