题型:阅读选择 题类: 难易度:普通
浙江省J12共同体联盟校2023-2024学年九年级下学期期中英语试题
Long ago, people didn't need a lot of numbers, but when small villages grew into big cities, people started to need bigger numbers to count bags of crops and make trades. How did people in ancient time count numbers?
Paclfic Islands Some Pacific Island cultures count using the whole body. Different body parts stood for a different number, and the name of that part also means that number. | Rome Greek, Roman, and Hebrew mathematicians used letters for their numbers, The Romans, for example, used I for 1, V for 5, X for 10, L for 50, C for 100, and M for 1,000. To write 49, it took nine letters: XXXXVIIII. | Peru In South America, the Inca came up with a different way to note down numbers — by making knots on ropes. Different kinds of knots stood for different numbers, while the color of the rope may have showed what was being counted. | |
Maya Math The Maya of Central America (200-900 CE) were great mathematicians. They counted in groups of 20. They wrote their numbers from bottom to top, with the bottom row standing for one time (1s), the next row up for 20 times (20s), then 400 times (400s), and so on. They used bean-shaped dots● for 1, twig-shaped lines for 5, and they even had a shell shaped symbol for 0! |
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