%转小数
Section outline
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A survey was conducted in 2014 to determine what percent of their income Americans give to charity. The responses to the survey revealed that Americans give 4.2% of their gross income to charity. That means that 95.8% of their gross income is not given to charity. How could you write these two percentages as decimals?
::2014年进行了一项调查,以确定美国人给慈善机构的收入占其收入的百分比。 对调查的答复显示,美国人给慈善机构的总收入占其总收入的4.2%。 这意味着其总收入的95.8%不给慈善机构。 你如何将这两个百分比写成小数?In this concept, you will learn to write percents as decimals.
::在此概念中,您将学习以小数位数来写百分数。Writing Percents as Decimals
::将百分比写入十进制Decimals represent a part of a whole just like fractions and percents do. You are able to write and . You can also convert a decimal to a percent and a percent back to a decimal again.
::十进制数代表整体的一部分,就像分数和百分数一样。您可以写作,也可以将小数点转换为百分数,再将百分数转换为十进制。A decimal organizes numbers according to place value . When you write a decimal as a percent, you also keep track of the place value.
::小数点按地点值排列数字。当将小数点写成百分比时,也会跟踪地点值。A percent is a part of a whole out of 100. Well, so is a decimal.
::百分之一是整部的一部分 出100 好吧,也是小数点。Let’s see if you can make better sense of the connection between a decimal and a percent.
::让我们看看您能否更清楚地理解小数点和百分比之间的关联。0.52
This decimal states that you have 52 hundredths. The percent sign means “out of 100” so you have 52 hundredths or 52 parts out of 100.
::这个小数点表示您有5200位数。 百分数符号表示“ 超过100位数 ” , 这样您就有5200位数, 即每100位数中52位数。Once you see the connection, you can write this and all decimals as a percent.
::一旦看到连接,你可以以百分比来写这个和所有小数。Both mean that you have 52 parts out of 100.
::两者都意味着在100分中有52分You move the decimal point two places to the right to show hundredths. Percent is “out of 100,” so the % sign is the same as two decimal places: .
::您将小数点 2 点移到显示第一百位的右侧。 百分率是“ 出于100, ” 所以 % 符号与小数点后两位相同: 0. 52 × 100 = 52 。Let’s look at how you write any percent as a decimal.
::让我们看看您如何以十进制写出任何百分比。First, drop the % symbol.
::首先, 降低% 符号 。Then, move the decimal point two places to the left.
::然后,将小数点两点移到左边。Finally, add zeros to the right of the decimal point as placeholders, if necessary.
::最后,必要时在小数点作为占位符的权利上加上零。Let’s take a look at another example.
::让我们看看另一个例子。Write 9% as a decimal. First, drop the % sign.
::将9%写为小数点。 首先, 降低% 符号 。9
Next, move the decimal point two places to the left. Because 9 is only one digit, you have to add a placeholder zero to show the two decimal places.
::接下来,将小数点 2 位移到左边。因为 9 位数只有一位数, 您需要添加一个占位符 0 以显示小数点后两个位数 。0.09
The answer is 9% written as a decimal is 0.09.
::回答是,小数点后,9%的回答是:0.09。Let’s look at one final example.
::让我们看看最后一个例子。Write 35.5% as a decimal.
::小数点后写35.5%。First, drop the % sign. 35.5
::首先,降低% 信号。 35.5Next, move the decimal point two places to the left.
::下一步,将小数点 2 位移到左边。0.355
The answer is written as a decimal, 35.5% is 0.355.
::答案以小数小数写,35.5%为0.355。Examples
::实例Example 1
::例1Earlier, you were given a problem about the charitable giving survey.
::早些时候,有人给了你一个关于慈善捐赠调查的问题In 2014, it was determined that Americans give 4.2% of their gross income to charity. That means they do not give 95.8% of their income to charity. How would you write each of these percents as a decimal?
::2014年,美国决定将其总收入的4.2%用于慈善。 这意味着他们不会将其收入的95.8%用于慈善。 你会如何将这些百分比写成小数?First, let’s work with 4.2%. Drop the % sign.
::首先,让我们用4.2%来工作。 放弃% 符号 。4.2
Next, move the decimal point two places to the left. Because 4 is only one digit, you have to add a placeholder zero to show the two decimal places.
::下一步,将小数点 2 位移到左边。由于 4 位数仅为一位数,您必须添加一个占位符 0 以显示小数点后两个位数。0.042
The answer is 4.2% written as a decimal is 0.042.
::回答是4.2%,小数点后写为0.042。Now let’s work with 95.8%.
::现在让我们用95.First, drop the % sign.
::首先, 降低% 符号 。95.8
Next, move the decimal point two places to the left.
::下一步,将小数点 2 位移到左边。0.958
The answer is 95.8% written as a decimal is 0.958.
::回答是小数点后,95.8%的回答是0.958。Example 2
::例2Write 25% as a decimal.
::小数点后写25%。First, drop the % sign.
::首先, 降低% 符号 。25
Although you can’t see it, the decimal point falls immediately to the right of any whole number.
::虽然你看不到, 但小数点会立即掉到任何数字右侧。Next, move the decimal point two places to the left. This is the hundredths place. Remember that two places is hundredths. You just dropped the percent sign, which means out of 100, so your answer has to reflect “out of 100” in a different way.
::接下来,将小数点两点移到左边。 这是第一百个地方。 记住, 两点是第一百个。 您刚刚掉了百分数符号, 也就是说在百分数中, 您的回答必须以不同的方式反映“ 百分数 ” 。0.25 The answer is 25% written as a decimal is 0.25.
::0.25 答案是25%,小数点后写为0.25。Example 3
::例3What is 35% written as a decimal?
::小数点后写出35%是多少?First, drop the % sign.
::首先, 降低% 符号 。35
Next, move the decimal point two places to the left.
::下一步,将小数点 2 位移到左边。0.35
The answer is 35% written as a decimal is 0.35.
::回答是35%,小数点后写为0.35。Example 4
::例4What is 2% written as a decimal?
::2%写为小数点是多少?First, drop the % sign.
2
::首先,放下% 符号 。Next, move the decimal point two places to the left. Because 2 is only one digit, you have to add a placeholder zero to show the two decimal places.
::下一步,将小数点 2 移到左边。因为 2 只有一位数, 您需要添加一个占位符 0 来显示小数点后两个位数 。0.02
The answer is 2% written as a decimal is 0.02.
::答案是2%,小数点后写为0.02%。Example 5
::例5What is 18.7% written as a decimal?
::18.7%的小数点是多少?First, drop the % sign.
::首先, 降低% 符号 。18.7
Next, move the decimal point two places to the left.
::下一步,将小数点 2 位移到左边。0.187
The answer is 18.7% written as a decimal is 0.187.
::回答是小数点小数点时18.7%是0.187。Review
::回顾Write the following percents as decimals.
::将以下百分数写为小数点。- 12%
- 15%
- 3%
- 67%
- 18%
- 78%
- 34%
- 7%
- 6%
- 36%
- 28%
- 33.5%
- 18.5%
- 13.25%
- 6.75%
Review (Answers)
::回顾(答复)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 。Resources
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