第4课：货币操作和税收
录像课 
In this lesson you will learn about money: 美元s and cents.
这个单词“dollar”相当老，是该词的修改版本“thaler”. Thaler is what coins were called back in 1519 in Chech Republic. Later on, the English version of the name (dollar) was also applied to similar coins. Not only ones minted in central Europe but also the Spanish 要么 Portuguese money. The Spanish peso 要么 美元 were widely used in Britain’的北美殖民地，因为缺少官方的英国硬币。因此，在美国独立后，“dollar” was chosen as the name of its currency instead of keeping the British pound. There are many different theories regarding the 要么 igin of the symbol used to represent a 美元 ($).
您将学到什么
You will discover that 1 美元 equals 100 cents and that cents can be expressed as part of a 美元 using 分数 要么 小数点 （0.05美元= 5美分）。
You will learn and practice how to add and subtract 美元s and cents, as well as how to multiply and divide them. For example, if one item costs $2 and 50 cents and the other item costs $3 and 14 cents, what is the total cost of both items? We would add 美元s and cents separately and get: $2 + $3 = $5; 50 cents + 14 cents = 64 cents. The total cost is $5 and 64 cents.
本课程讲授如何根据数字的位数对数字进行分组，以便在没有计算器的情况下更快地用钱进行操作。
它还讨论了销售税以及如何在购买时计算总价以找到总计。营业税是客户在商品的实际价格之上支付的税款。在某些国家/地区，价格会立即包含在其中，而在其他国家/地区，则需要在结帐时进行计算并添加。
