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老师问:“0.5=0.50吗?”一个同学说:“是的,但是它们表示的意义不同。”的确,0.5表示把一个正方形平均分成10份取5份,0.50则表示把同一个正方形平均分成100份取50份。由此可以概括出小数的性质:小数的末尾添上0或者去掉0,小数的大小不变。因此,遇到小数末尾有0的时候,一般可以去掉,把小数化简。但要注意:0.5和0.50在这里都是表示小数的准确值,小数末尾有无0仅仅表示把同一个整体“1”平均分的份数不同(即表示小数的位数不同)而它们的大小是不变的。所以,0.5=0.50。而在小数运算中,得数往往要求用“四舍五入”法,保留一定的小
The teacher asks: “0.5 = 0.50?” One classmate said: “Yes, but they have different meanings.” Indeed, 0.5 means dividing a square into five equally divided by 10, and 0.50 means An average square divided into 100 50 copies. This can be summarized as the nature of the decimal: the end of the decimal add 0 or 0, the size of the decimal unchanged. Therefore, when there is 0 at the end of the decimal, you can generally remove it and simplify the decimal. Note, however, that 0.5 and 0.50 are the exact values of the decimal, and the zero at the end of the decimal means only the difference in the number of copies of the same whole “1 ” (that is, the number of decimal places is different) and that they The size is the same. So, 0.5 = 0.50. In fractional operations, the number is often required to use “rounding ” method, to retain a certain small