6.10小百分比和大百分比作为小数

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  小百分比和大百分比作为小数

  

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  The largest insect is the Giant Walking Stick, which can be as much as 254,000% the size of the smallest insect, the fairyfly, a member of the wasp family. Conversely, the fairyfly measures a mere 0.03937% the size of the largest Giant Walking Stick. How could you write these percents as decimals?
  ::最大的昆虫是巨型漫步棍,它可以比最小的昆虫小到254000 % , 仙女, 黄蜂家族的成员。相反,仙子的大小只比最大的巨型漫步棍小到0.039337 % 。 您如何将这些百分比写成小数?

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  In this concept, you will learn how to write percents that are less than one and more than 100 as decimals.
  ::在此概念中, 您将学习如何写入小数位数小于一个且超过100的百分位数 。

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  Writing Small and Large Percents as Decimals
  ::将小和大百分比写入十进制

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  Sometimes, you will have a percent that is part of one whole. Such percents will be very tiny.
  ::有时候,你会得到一个整体的一部分。这样的百分比会非常小。

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  How would you write the percent 0.5% as a decimal?
  ::你如何将0.5%的百分率写成小数点?

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  This is another way of saying one-half of a percent, or  $\begin{array}{r}1\mathrm{\%}÷2\end{array}$ . It is therefore smaller than one percent.
  ::这是另一种说法,即 一半或1% 或2%。因此,它小于1%。

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  You can also have a percent that is greater than one hundred. Such percents are very large—so large, in fact, that they are more than one whole.
  ::您也可以拥有超过100%的百分率。这些百分率非常大 — — 事实上非常大,以至于它们不止是一个整体。

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  300% is one of those percents.
  ::300%是其中之一。

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  This percent is three times 100 percent, or three wholes.
  ::这百分之三是百分之三的三倍, 或三整。

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  Let’s look at changing percents like these to decimals.
  ::让我们看看这些百分比变化到小数点。

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  When converting percents between 1% and 100% to decimals, you:
  ::当1%至100%之间的百分比转换到小数点时,您:

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  1. Drop the % sign.
     ::放弃% 符号 。
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  2. Move the  decimal point  two places to the left. Use  zero  placeholders as needed.
     ::将小数点 2 位移到左边。必要时使用零占位符。

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  Now let’s apply these steps to larger and smaller percents.
  ::现在让我们把这些步骤应用到更大和较小的百分比上。

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  Let’s try an example.
  ::让我们以身作则。

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  Write 0.5% as a decimal. First, drop the percent sign.
  ::将0.5%写为小数点,首先,降低百分数符号。

  $\begin{array}{r}0.5\end{array}$  

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  Next, move the decimal point two places to the left.
  ::下一步,将小数点 2 位移到左边。

  $\begin{array}{r}0.005\end{array}$

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  The answer is 0.5% written as a decimal is 0.005.
  ::答案是0.5%,小数点后写为0.005。

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  Let’s look at another example.
  ::让我们再看看另一个例子。

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  Write 350% as a decimal. First, drop the percent sign. 350
  ::将350%写为小数小数。 首先,降低百分数符号 350

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  Next, move the decimal point two places to the left.
  ::下一步,将小数点 2 位移到左边。

  $\begin{array}{r}3.5\end{array}$

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  The answer is 350% written as a decimal is 3.5.
  ::回答是350%,小数小数是3.5。

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  Examples
  ::实例

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  Example 1
  ::例1

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  Earlier, you were given a problem about the Giant Walking Stick.
  ::早些时候,有人给了你一个关于巨人漫步棒的问题

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  This insect is up to 254,000% the size of the fairyfly. Conversely, the fairyfly is 0.03937% the size of the largest Giant Walking Stick. How could you write these percents as decimals?
  ::这只昆虫的大小高达仙子的254,000 % 。 相反,仙子的大小是巨人漫步棒的0.03937%。 您如何将这些百分数写成小数?

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  Let’s rewrite 254,000% first. First, drop the percent sign.
  ::让我们先重写254,000 % 。 首先, 降低百分比符号 。

  $\begin{array}{r}254,000\end{array}$

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  Next, move the decimal point two places to the left.
  ::下一步,将小数点 2 位移到左边。

  $\begin{array}{r}2,540.00\end{array}$

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  You can drop the zeroes after the decimal point because they have no value.
  ::您可以在小数点后降低零,因为零没有值。

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  The answer is 254,000% written as a decimal is 2,540.
  ::回答是小数点后写为254,000%,小数点后写为2,540。

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  Now, let’s rewrite 0.03937% as a decimal. First, drop the percent sign.
  ::现在,让我们将0.03937%重写为小数点。 首先,降低百分数符号。

  $\begin{array}{r}0.03937\end{array}$  

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  Next, move the decimal point two places to the left.
  ::下一步,将小数点 2 位移到左边。

  $\begin{array}{r}0.0003937\end{array}$

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  The answer is 0.03937% written as a decimal is 0.0003937.
  ::回答是 0.03937% 以小数小数写为 0.003937。

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  Example 2
  ::例2

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  A company that produces light bulbs is very proud of the fact that only 0.02% of each shipment is defective. Write this percent as a decimal.
  ::生产灯泡的公司对每批发货中只有0.02%有缺陷这一事实感到非常自豪。 将这个百分比写为小数点。

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  To write this percent as a decimal, simply follow the steps. First, drop the percent sign.
  ::将这个百分比写为小数点, 只需跟随步骤。 首先, 降低百分比符号 。

  $\begin{array}{r}0.02\end{array}$

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  Next, move the decimal point two places to the left.
  ::下一步,将小数点 2 位移到左边。

  $\begin{array}{r}0.0002\end{array}$

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  The answer is 0.0002 of each shipment is defective.
  ::答案是每批货物有缺陷 每批货物的答案是0.0002

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  Example 3
  ::例3

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  Write 0.25% as a decimal. First, drop the percent sign.
  ::小数点后写0.25%。首先,降低百分数符号。

  $\begin{array}{r}0.25\end{array}$

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  Next, move the decimal point two places to the left.
  ::下一步,将小数点 2 位移到左边。

  $\begin{array}{r}0.0025\end{array}$

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  The answer is 0.25% written as a decimal is 0.0025.
  ::回答是小数点后写为0.0025的0.25%。

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  Example 4
  ::例4

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  Write 450% as a decimal. First, drop the percent sign.
  ::450%写小数,首先,降低百分数符号。

  $\begin{array}{r}450\end{array}$

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  Next, move the decimal point two places to the left.
  ::下一步,将小数点 2 位移到左边。

  $\begin{array}{r}4.5\end{array}$

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  The answer is 450% written as a decimal is 4.5.
  ::答案是小数小数小数的450%是4.5。

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  Example 5
  ::例5

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  Write 675% as a decimal. First, drop the percent sign.
  ::小数点后写出675%。首先,降低百分数符号。

  $\begin{array}{r}675\end{array}$

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  Next, move the decimal point two places to the left.
  ::下一步,将小数点 2 位移到左边。

  $\begin{array}{r}6.75\end{array}$

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  The answer is 675% written as a decimal is 6.75.
  ::回答是小数点小数点小数点后675%的回答是6.75。

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  Review
  ::回顾

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  Rewrite each percent as a decimal.
  ::每一百分比重写为十进制。

  1. 0.34%
  2. 0.5%
  3. 350%
  4. 650%
  5. 0.30%
  6. 0.10%
  7. 0.09%
  8. 0.22%
  9. 230%
  10. 500%
  11. 700%
  12. 0.012%
  13. 0.04%
  14. 0.6%
  15. 0.16%

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  Review (Answers)
  ::回顾(答复)

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  Click   to see the answer key or go to the Table of Contents and click on the Answer Key under the 'Other Versions' option.
  ::单击可查看答题键, 或转到目录中, 单击“ 其他版本” 选项下的答题键 。

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  Resources
  ::资源