Section outline

  • lesson content

    Sarah is cleaning up after an art project. There are two boxes that still have clay in them. One box is  1 5  full. The other box is  3 5  full. How much clay is leftover? Can she combine the leftover clay into one box?
    ::Sarah正在清理一个艺术工程。 有两个盒子里还有粘土。 一个盒子里满了15个。 另一个盒子里满了35个。 剩下多少粘土? 她能把剩下的粘土合并成一个盒子吗 ?

    In this concept, you will learn how to add fractions with  like denominators .
    ::在这个概念中,你将学会如何添加分数和类似分母。

    Adding Fractions with Like Denominators
    ::添加像分数一样的分数

    Adding fractions with the same  denominator  is easy.  Fractions with the same denominators are said to have like or  common denominators . This means that the whole has been divided up into the same number of parts. If the denominator of two fractions is a six, then both of those fractions have been divided into six parts. The parts of each fraction are equivalent.
    ::使用相同分母添加分数是很容易的。 使用相同分母的分数据说有相似的或共同的分母。 这意味着整块被分成相同数量的部分。 如果两个分母的分母是六, 那么这两个分母都分为六部分。 每个分母的分母是等同的。

    This picture shows two different fractions with like denominators.
    ::此图显示两个不同的分数, 有相似分母 。

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    lesson content

    To add these two fractions, add the parts. Remember that the part in a fraction is the  numerator . Here it is as a picture.
    ::添加这两个分数时, 请添加各个部分。 记住, 分数中的部分是分子。 这里是图像 。

      

    lesson content

    2 6 + 4 6 = 6 6

    The  sum  of both fractions is six-sixths. In this example, you can  simplify  or  reduce  the fraction to one whole. You can see that one whole figure is shaded in.
    ::两个分数的总和是六六分之六。在此示例中,您可以将分数简化或压缩为一个整体。您可以看到一个整数被阴影遮蔽。

    6 6 = 1

    Therefore, the sum is 1.
    ::因此,数额为1。

    Let’s look at another addition problem.
    ::让我们看看另一个附加问题。

    2 8 + 4 8 = _

    The first step is to check if the fractions have a  common denominator . Both denominators are 8. Then, add the fractions. The sum of the fractions is the sum of the numerators over the common denominator. 
    ::第一步是检查分数是否有共同的分母。 两个分母都是 8 。 然后, 添加分数。 分数的总和是共同分母上的分子总和 。

    2 + 4 = 6

    The sum of the numerators is 6. Put the sum over the common denominator. 
    ::计数器的总和是6. 将总和置于共同分母之上。

    6 8

    Next, write the fraction in  simplest form . 6 and 8 have the   (GCF) of 2.  Divide  both the numerator and the denominator by 2 to simplify the fraction. If the GCF is 1, the fraction is already in simplest form. 
    ::接下来,以最简单的形式写出分数。 6和8的分数为 2 的(GCF) 。 将分子和分母除以 2 以简化分数。 如果 GFP为 1, 则分数已经以最简单的形式出现 。

    6 ÷ 2 8 ÷ 2 = 3 4

    The sum is  \frac{3}{4} .
    ::数额是。

    Remember that when adding fractions, you are only adding the parts of the whole. The denominator remains the same. 
    ::记住, 当添加分数时, 您只是在添加整体的各个部分。 分母保持不变 。

    Examples
    ::实例

    Example 1
    ::例1

    Earlier, you were given a problem about Sarah and the leftover clay.
    ::早些时候,你曾为莎拉和剩下的粘土感到困扰。

    Sarah needs to combine one box that is  1 5  full and another box that is  3 5  full. Add the fractions to find the total  amount  of leftover clay.
    ::Sarah需要将一个15整箱和另一个35整箱合并。添加分数以找到剩余粘土的总量。

    First, check if the fractions have a common denominator. Both denominators are 5.
    ::首先,检查分数是否有共同的分母。 两个分母都是5。

     Then, add the fractions. Find the sum of the numerators over the common denominator.
    ::然后,添加分数。在共同分母上找到分子的总和。

      1 + 3 = 4 4 5

    The fraction is in simplest form.
    ::分数以最简单的形式出现。

    There is  4 5  box of clay left. Sarah can fit the leftover into one box.
    ::剩下45箱粘土 Sarah可以把剩菜放进一个盒子里

    Example 2
    ::例2

    Find the sum. Answer in simplest form.
    ::找到金额,回答最简单

      3 10 + 2 10 + 2 10 = _ .

    First, check if the fractions have a common denominator. All the denominators are 10.
    ::首先,检查分数是否有共同分母。所有分母为10。

    Then, add the fractions. Find the sum of the numerators over the common denominator.
    ::然后,添加分数。在共同分母上找到分子的总和。

      3 + 2 + 2 = 7 7 10

    The fraction is in simplest form.
    ::分数以最简单的形式出现。

    The sum is  7 10 .
    ::总额是7 10。

    Example 3
    ::例3

    Find the sum:  1 7 + 2 7 = _ . Answer in simplest form.
    ::查找总和: 1 7+ 2 7 = _. 回答最简单。

    First, check if the fractions have a common denominator. Both are 7.
    ::首先,检查分数是否有共同的分母。这两个分母都是7个。

    Then, add the fractions. Find the sum of the numerators over the common denominator. 
    ::然后,添加分数。在共同分母上找到分子的总和。

      1 + 2 = 3 3 7

    The fraction is in simplest form.
    ::分数以最简单的形式出现。

    The sum is  3 7 .
    ::总共是3 7。

    Example 4
    ::例4

    Find the sum:  3 9 + 1 9 = _ . Answer in simplest form.
    ::查找总和: 3 9 + 1 9 = _. 回答最简单。

    First, check if the fractions have a common denominator. Both are 9.
    ::首先,检查分数是否有共同的分母。这两个分母都是9个。

    Then, add the fractions. Find the sum of the numerators over the common denominator. 
    ::然后,添加分数。在共同分母上找到分子的总和。

      3 + 1 = 4 4 9

    The fraction is in simplest form.
    ::分数以最简单的形式出现。

    The sum is  4 9 .
    ::金额是4 9。

    Example 5
    ::例5

    Find the sum:  2 10 + 3 10 = _ . Answer in simplest form.
    ::查找总和: 2 10+ 3 10 = _. 回答最简单。

    First, check if the fractions have a common denominator. Both are 10.
    ::首先,检查分数是否有共同的分母。这两个分母都是10个。

    Then, add the fractions. Find the sum of the numerators over the common denominator.
    ::然后,添加分数。在共同分母上找到分子的总和。

      2 + 3 = 5 5 10

    Next, simplify the fraction. The GCF of 5 and 10 is 5. Divide the numerator and the denominator by 5.
    ::接下来,简化分数。全球合作框架5和10是5,分子和分母除以5。

      5 10 = 1 2

    The sum is  1 2 .
    ::金额是12。

    Review
    ::回顾

    Find the sum. Answer in simplest form.
    ::找到金额,回答最简单

    1. 1 3 + 1 3 = _
    2. 2 5 + 2 5 = _
    3. 4 7 + 2 7 = _
    4. 5 11 + 4 11 = _
    5. 6 10 + 1 10 = _
    6. 4 10 + 1 10 = _
    7. 3 4 + 1 4 = _
    8. 5 6 + 3 6 = _
    9. 4 9 + 2 9 = _
    10. 5 10 + 1 10 = _
    11. 6 13 + 4 13 = _
    12. 9 10 + 1 10 = _
    13. 6 9 + 1 9 = _
    14. 8 12 + 1 12 = _
    15. 10 20 + 4 20 = _
    16. 11 18 + 5 18 = _

    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
    ::资源