4.4 总体调查百分比-interactive

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  发现整个 给定百分比

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  Battery Life
  ::电池生命

  

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  Cell phones and computers use percentages to indicate remaining battery life. This percentage indicates the time that the user has left on the device before the battery runs out compared to the life of the battery.
  ::手机和计算机使用百分比表示剩余电池使用寿命,这个百分比表示用户在电池用完之前留在电池上的时间,与电池使用寿命相比。

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  Discussion Question
  ::讨论问题

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  If a cell phone battery at 22% takes 176 minutes to run out, how can we use this information to find the life of the battery at 100% when it is fully charged? 
  ::如果22%的手机电池耗时176分钟,

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  Consider  the question asked above using a tape diagram.
  ::使用磁带图考虑上文提出的问题。

  

  INTERACTIVE

  Battery Life

  

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  When a phone is overcharged sometimes a battery pack is used to store all the extra energy.
  ::当电话充电过量时 有时用电池包 储存所有多余的能量

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  • Move the slider to see how much of the battery is charged.
    ::移动滑动器以查看电池充电量 。

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  Please check your internet connection and try again.

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  Discussion Question
  ::讨论问题

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  What do you think the full battery life of the phone is based on estimation ?
  ::你认为电话的电池完整寿命 是基于什么估计?

    

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  S olve this using the  formula   $\begin{array}{r}\text{percent}\cdot \text{whole = part}.\end{array}$  The percent must be written either as a decimal or a fraction when using this formula.
  ::使用公式% = part 来解决这个问题。 使用此公式时, 百分比必须以小数点或小数表示 。

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  • Part = 176
    ::第176部分=176
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  • Whole = ?
    ::整个?
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  • Percent = 22% → 0.22
    ::百分比=22% = 0.22

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  $\begin{array}{rl}\text{percent}\cdot \text{whole}& =\text{part}\\ 0.22\cdot x& =176\\ x& =176/0.22\\ x& =800\end{array}$
  ::百分百= part0.22x= 176x= 176/0.22x= 800

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  Answer: 800 minutes
  ::答复:800分钟

  ercent-problems" quiz-url="https://www.ck12.org/assessment/ui/embed.html?test/view/5f457850e8368a469d40e3f9&collectionHandle=algebra&collectionCreatorID=3&conceptCollectionHandle=algebra-:ercent-problems&mode=lite" test-id="5f457850e8368a469d40e3f9">

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  A Slice of Pie 
  ::馅饼的切片

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  A local government released  the pie graph below detailing its spending in various areas. 
  ::地方政府在下文中公布馅饼图,详细说明其在各领域的支出。

  

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  Based on the information above, if the local government spent $24,000,000 on police and corrections  which represented 6% of the budget, how much total money was spent?
  ::根据上述资料,如果地方政府在警察和惩戒方面花费24 000 000美元,占预算的6%,那么花费的总额是多少?

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  U se the  formula   $\begin{array}{r}\text{percent}\cdot \text{whole = part}\end{array}$  to determine this.
  ::使用公式百分率=部分来决定这一点 。

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  • Percent = 0.06
    ::百分比=0.06
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  • Whole = ?
    ::整个?
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  • Part = 24,000,000
    ::=24 000 000

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  $\begin{array}{rl}\text{percent}\cdot \text{whole}& =\text{part}\\ 0.06\cdot x& =24,000,000\\ x& =24,000,000/0.06\\ x& =400,000,000\end{array}$
  ::= 24 000 000x= 24 000 000/0.06x= 400 000 000

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  Answer: $400,000,000
  ::答复:400 000 000 000美元

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  A survey was given to different groups of people about what their favorite type of movie is: romance, science-fiction, action, comedy, drama. Use the interactive below to find the number of people in each sample based on the results.
  ::对不同群体的人进行了调查,了解他们最喜欢的电影类型是什么:浪漫、科学小说、动作、喜剧、戏剧。使用下面的交互效果,根据结果来查找每个样本中的人数。

  

  INTERACTIVE

  A Slice of Pie

  

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  • Click on a section of the pie graph to see information about that part.
    ::点击馅饼图的某个部分查看关于该部分的信息 。
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  • Enter the total number of people sampled into the box based on the information given.
    ::根据所提供的信息输入框中抽样的总人数。

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  Please check your internet connection and try again.

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  Yes

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  Discussion Question
  ::讨论问题

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  When solving the problem above, Donna found it easier to start with smaller percentages and Ellie found it easier to start with multiples of 10. Who do you side with and why? Use evidence or an example to support your answer.
  ::当解决上述问题时,唐娜发现从较低百分比开始比较容易,艾莉发现从10的倍数开始比较容易。你支持谁,为什么?使用证据或范例来支持你的回答。

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  Increase and Decrease
  ::增加和减少

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  You  can use  the same approach from above to find the whole when dealing with problems involving an increase or decrease.
  ::在解决涉及增减的问题时,您可以从上而下地使用同一方法找到整个问题。

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  Example
  ::示例示例示例示例

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  A newspaper company held a meeting to discuss sales. One employee says that yearly sales revenue has dropped by 45% over the past ten years and that this year is only 55% of what it was ten years ago. You know that this year the annual revenue this year was $990,000. What was the yearly revenue ten years ago?
  ::一家报纸公司举行会议讨论销售问题。 一位雇员说,过去十年年销售收入下降了45%,今年仅为十年前的55%。 你知道今年的年收入是990,000美元。 十年前的年收入是多少?

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  You  can use the equation  $\begin{array}{r}\text{percent}\cdot \text{whole = part}\end{array}$  to determine this. However, 45% represents the amount that sales decrease and $990,000 represents the sales remaining so you cannot use both in the formula. You must either find the percent remaining or the amount of the decrease.
  ::您可以使用方程式%- 整体 = 部分来确定这一点。 但是, 45%代表销售额下降的数额, 990,000代表剩余销售额, 这样您在公式中无法同时使用。 您必须找到剩余百分比或下降数额 。

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  Since  you know that sales  decreased by 45% from 100%,  you can find the percent remaining by subtracting 45% from 100%. This will tell you that $990,000 represents the 55% remaining after the 45% decrease.
  ::既然你知道销售额从100%下降45%,那么通过从100%中减去45%,就可以找到剩余部分。这将告诉你,990,000美元是45%下降后剩余的55%。

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  • Percent = 55% → 0.55
    ::百分比=55% = 0.55
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  • Whole = ?
    ::整个?
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  • Part = 990,000
    ::=990 000

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  $\begin{array}{rl}\text{percent}\cdot \text{whole}& =\text{part}\\ 0.55\cdot x& =990,000\\ x& =\frac{990,000}{0.55}\\ x& =1,800,000\end{array}$
  ::=0.55x=990,000x=990,900.55x=1,800,000

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  Answer: $1,800,000
  ::答复:1 800 000美元

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  Discussion Question
  ::讨论问题

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  Is there a different way to solve the problem above? Use algebra to prove that the two methods are equivalent.
  ::是否有不同的办法来解决上述问题?使用代数来证明这两种方法是等效的。

  Summary

  播放段落 Rearrange the formula $\begin{array}{r}\text{percent}=\frac{\text{part}}{\text{whole}}\end{array}$ to solve problems involving percentages. ::重新排列公式百分比=全方位,以解决涉及百分比的问题。 播放段落 You can convert a percentage into a decimal by dividing by 100. For example, 87% can be represented by the decimal value 0.87. ::您可以将百分数除以100将百分数转换为十进制数,例如,小数值0.87可以表示87%。