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第九单元

2021-5-31 10:31| 发布者: admin| 查看: 116| 评论: 0

摘要: .

Unit 9

I'm a little cook——The preliminary understanding of fractions

我当小厨师——分数的初步认识

Lesson 1

Cooperative exploration

合作探索

1. Each child can get half of the moon cake. How about half?

1. 每个小朋友能分得这个月饼的一半，一半怎样表示？

One half is written as 1/2. It is pronounced as one half

一半用1/2表示，读作：二分之一

2.What does 1/2 mean?

1. 1/2是什么意思？

Divide a ○ into two equal parts, and one is one half of it.

把一个○平均分成2份，一份就是它的二分之一。

3. Divide a baked cake into 4 equal parts. How much is each piece?

1. 把一个烧饼平均分成4份，每份是多少？

I'm going to use a round piece of paper to represent the pancake, and I'm going to divide it into four equal pieces, so each piece is going to be a quarter of it.It is indicated by 3/8.

我用一张圆形纸片表示烧饼，把它平均分成4份，每份就是它的四分之一，用1/4表示。

4.Divide a cake into eight equally. How much does three equal?

1. 把一个蛋糕平均分成8份，3份是多少？

I'm going to use a round piece of paper to represent the cake, and I'm going to divide it evenly into 8 pieces, so each piece is one eighth of it, and 3 pieces is three eighth of it.It is indicated by 3/8.

我用一张圆形纸片表示蛋糕，把它平均分成8份，每份是它的八分之一，3份就是它的八分之三，用3/8表示。

Like 1/2, 1/4, 1/8, 3/8...... Numbers like this are all fractions.

像1/2、1/4、 1/8、 3/8......这样的数，都是分数。

分子： Numberator 分数线：fractional line 分母：Denominator

Lesson 2

Xiao Dong ate five eighth of the orange.

小东吃了这个橙子的5/8。

Xiao Li ate three eighth of the orange.

小利吃了这个橙子的3/8。

What questions can you ask?

你能提出什么问题？

合作探索