分数和十进数之间的转换

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Topple Over
::翻翻翻

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Think back to the definition of a fraction, a portion of something or a part of the whole . These phrases imply that a fraction is division. To convert a fraction into a decimal, that is exactly what you do. Recall that the numerators and denominators of any fraction is a whole number or integer. If the fraction is negative, then either the numerator or denominator is negative.
::回想一下一个分数、某物的一部分或整个的一部分的定义。这些短语意味着一个分数是分数。要将一个分数转换成小数,这就是你要做的。提醒注意,任何分数的分数和分母是一个整数或整数。如果分数为负数,则数字或分母为负数。

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To change a fraction into a decimal, you need to d ivide the numerator by the denominator. An easy way to remember this is to say, "top in, bottom out."
::要将分数修改为小数点, 您需要将分子除以分母。 很容易记住的方法就是说, “ 顶部, 底部 ” 。

 

 

 

 

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Here, you were introduced to a new type of decimal, a repeating decimal .  Repeating decimals go on forever and repeat in a pattern. Once you notice that the decimal is repeating, you can stop. To write repeating decimals, put a bar over the top of the numbers that repeat.  For example ,  $\begin{align*}\tfrac{2}{3}=0.\overline{6}\end{align*}$  ,  $\begin{align*}\tfrac{2}{9} = 0.\overline{2}\end{align*}$  , and  $\begin{align*}\tfrac{4}{15}=0.2\overline{6}.\end{align*}$  Notice that only the 6 has the repeating bar over it, because only the 6 continues on. If a decimal stops and does not repeat, it is called a terminating decimal .  
::在此, 您被引入一种新的小数点, 重复小数点。 重复小数点会永远持续, 并在模式中重复。 一旦您注意到小数点正在重复, 您可以停止。 要写重复小数点, 请在重复的数字顶部加一栏。 例如, 23=0. 0. 6, 29=0. 2, 415=0. 2 。 注意只有 6 点上面有重复栏, 因为只有 6 点继续。 如果小数点停止, 不重复, 则称为终止小数点 。

 

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Decimals as Fractions
::十进数作为分数

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The fractions shown have denominators of 100, 10 and 5.
::所显示的分数分母分母为100、10和5。

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Remember,  are fractions that reduce to the same fraction or have the same decimal value.
::记住,是小数点减到同一个小数点或小数点值相同的分数。

 

 

 

 

 

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Terminating or Repeating?
::终止还是重复?

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Use the interactive to match  the fractions and decimals in the table. Then, select either T for terminating decimals or R for repeating decimals in the last column.
::使用交互式互动来匹配表格中的分数和小数。然后选择 T 来终止小数,或者选择 R 来在最后一列重复小数。

 

 

 

 

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Discussion Question
::讨论问题

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Why do you think that some decimals repeat and some do not? List the divisors of numbers which result in repeating decimals and look for patterns.
::为什么你认为有些小数点重复而有些不重复?列出导致重复小数点和查找模式的数字的差数。