Lesson 2 Unit fraction (1)

Reflection of homework To find the relationship of the whole and part at home and say to your parents. Say: If …….. is the whole, then ……. is the part of the whole.

Review 1、Understand the whole and part and the relationship with them. 2、Divide the whole into several equal parts-------- Divide equally.

111×111＝ 12321 1111×1111＝ 1234321 11111×11111＝ 123454321 25 1+2+3+4+5+4+3+2+1＝ 1+2+3+4+5+6+5+4+3+2+1＝ 36 1+2+3+4+5+6+7+8+9+8+7+6+5+4+3+2+1 ＝ 81

Divided equally or not

Divided equally or not

Divided equally or not

One day Jone and I got 4 cakes One day Jone and I got 4 cakes. Jone said: ”I want to share them with you, so I get 3 cakes” Is it right? Can you divided equally? 2 Each gets ( ) cakes.

1 The second day Jone and I have got 2 cakes. Can you divided equally? Each one gets ( ) cake.

half The third day Jone and I got 1 cake. Can you divided equally? We each get ( ) cake.

1 3 1 3 1 2 1 2 1 3 1 4 1 4 1 4 1 4

1 2 How to write fractions： Numerator Fraction line Denominator 1st Fraction line 2nd Denominator 3rd Numerator are all fractions. 1 Numerator Fraction line 2 Denominator

１ － ２ Is it right？

１ － ２ half half We divide a whole into 2 equal parts, each part is of the whole,written as

3 1 ( ) － 3 We divide 1 cake into ( ) equal parts, each part is of the cake . 3 1 ( ) － 3

1 m ?

Lesson 2 Exercises 2. Match the picture with the fraction. 1 1 1 4 2 6

× × √ √ √ √ √ √ Lesson 2 Exercises 1. True or false: Is it divided equally? (“√”or “×”) × × √ √ √ √ √ √

Lesson 2 Exercises 3. Write down the fraction of the coloured part 1 6 1 4 1 3 1 5 1 4 1 4 1 4

Lesson 2 Exercises 1 4 1 4

Lesson 2 Exercises 1 4 1 4 1 4

Lesson 2 Exercises 4. True or false. (1) A rectangular piece of paper is divided into 7 parts of the same size, each part is . ( ) (2) Give a cake to 4 children, everyone get of the cake. ( ) (3) means that a whole average is divided into 5 parts, each part is of the whole.( ) 1 7 √ 1 4 × 1 5 √ 1 5

〉 〉 〉 Lesson 2 Exercises m( ) m m( ) m m( ) m 1 4 1 6 1 10 1 5 1 5 1

A fraction, if its numerate is 1, the fraction is also called unit fraction. 2 3 7 12 25 100 ……

Make

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☆☆☆ 3、Chanllege: Ture or false Revision & Exercises ☆☆☆ 3、Chanllege: Ture or false Whether the colored part express of the whole? ( )

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1 8 ( )

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