Bài 1: Fractions: phân số

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1,Have you ever heard of origami Starry?

2.No, origami is an art form of Japan where different objects and shapes are made using paper folding technique. .

3.You must be wondering why I’m asking you about origami.

4.Today we are going to use paper folding to learn a new topic in math.

5.See Starry, let’s take this round paper and fold it in such a way that we divide it into to equal parts. 

6.Now, let’s open the fold. We see a horizontal mark passing through the center. 

7.Let’s mark it with pencil. In how many part is the circle divided Starry? 

8.Yes, the circle has been divided into 2 equal parts. 

9.Now Starry, we shall colour 1 part of this circle red. 

10.So now we can say that one part out of two equal parts is coloured red. 

It can also be written as 1 over 2(1/2): 

One over two or haft is known as a fraction. 

So Starry, a fraction is a part of the whole. 

Now observe the folds made in this rectangular sheet. 

The rectangular sheet is divided in three equal parts. 

Let’s draw lines on the folds made. 

How many parts should we color? Ok, let’s color only one part. 

So we can say that one out of three parts are coloured. 

In the form of a fraction it can be written as 1 upon 3. 

Should we fold this square shape sheet now? 

OK. Here it is. How many equals part are formed? 
Yes, 4. Uh, Let’s colour 3 parts in this sheet. So we say that 3 parts out of 4 are coloured. 

Can you write the fraction of the coloured part? 

Yes, the fraction is 3 upon 4.

Starry, look at the picture of this cake. Into how many pieces in this cake cut? 

Yes, 8 equal pieces 

Now, support I eat 3 pieces of this cake. What part of the cake do I eat? 

Yes, 3 pieces out of 8 pieces means I eat 3 upon 8 parts of the cake. 

Look at the next picture Starry. 

Here the circle has been devided into 8 equal parts. 3 parts are coloured blue, 4 parts red and 1 part yellow. 

Can you tell me the fraction representing the blue coloured part.

Yes, 3 upon 8 parts are coloured blue. We can also write as 4 upon 8 part is coloured red. And 1 upon 8 part is coloured yellow. 

Starry, I know you like colouring. So let do an activity where we revise about fraction and also colour.

See, we have a few shapes cut out on a white paper. These shapes have also been devided into parts. 

We have to colour the part of the figure that is indicated by the fraction.

Let’s state the first shape. What fraction is mentioned here? 

Yes. 1 upon 2, so we shall colour 1 part out of the 2 parts. 

Now, consider the second shape. The fraction is 3 upon 4. That means it has been devided into 4 equal parts. How many parts shall we colour? Yes, 3 parts. 

In the next shape the fraction mentioned is 5 upon 7 , so we shall colour 5 parts out of the total 7 parts. Look at the last shape Starry, and how many parts have been devided ? 

Yes, 12. The fraction for the coloured part is 7 upon 12.  So how many parts shall we coloured? 

Yes, 7 parts.  .

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