Numbers: Everyone's language.
Ancient numbers
In ancient times, people wrote numbers in many different ways.However,they nearly all counted in tens.
Zero
The system of numbers today consists of the numbers from 1 to 9 and 0 (zero).The Indians first invented and developed the 1 to 9 system of numbers. They then invented the zero. This was a very important invention because it made it easier to write big numbers and to calculate.
Calculating machines
One of the first calculating machines was an abacus. Abacuses are fast and accurate,so people still use them today. On the abacus in the picture, the beads on the wires represent ones, tens,hundreds and thousands starting from the bottom wire.
Now,we use modern calculators.The picture on the right shows a modern calculator. It can add,subtract, multiply and divide. It can also calculate percentages and square roots.
參考答案:数字:大家的语言.
原始数字
远古时代,人们通过不同的方式记录数字，但是他们几乎都在10之内。
零
今天的数字系统包括数字1-9和0。印度人首先发明和发展了1-9的数字系统。不久他们又发明了0。之所以这是非常重要的发明，是因为它更容易去书写大数字并予以计算。
计算器
世界上第一个计算器是算盘。珠算计算方便准确，所以沿用至今。在珠算图上。珠算的计算从个、十、百、千位对应的珠子的底部开始。
现在，我们使用现代计算器。右图展示了一个现代的计算器。它能加减乘除。它还可以进行百分率和平方计算。
