Trong các tích có các thừa số chia hết cho 5 như:

25; 30; 35; 40; 45; 50

Hay 20 = 5 x 4; 25 = 5 x 5; 30 = 5 x 6; 35 = 5 x 7; 40 = 5 x 8; 45 = 5 x 9; 50 = 5 x 10

Mỗi thừa số 5 nhân với 1 chẵn ta được số tròn chục. Mà tích trên có 7 thừa số 5 nên tích tận cùng bằng 7 + 2 = 9 chữ số 0.

Vì các số như 25; 50 khi nhân với một số chia hết cho 4 sẽ có tận cùng 2 chữ số 0.

* Do ko thấy đề bài đầy đủ nên đoán bừa, sai xinloi ạ *

Hc tốt

Trong tích trên có các số \(⋮\)( chia hết )  5 là: 20 ; 25 ; 30 ; 35 ; 40 ; 45 ; 50.

Từ các chữ số trên ta có thể viết được các tích từ thừa số thứ (1) từ 5 là:

20 = 5 x 4 

25 = 5 x 5

30 = 5 x 6 

35 = 5 x 7 

40 = 5 x 8

45 = 5 x 9 

50 = 5 x 10 = 5 x 5 x 2 

Vậy ta có thể viết được 8 tích của các số chia hết cho 5 mà có 9 thừa số 5

=> Tích trên có 9 chữ số 0 ở tận cùng .

- Hok T - 

Bài 3: Tìm lỗi sai và sửa lại trong các câu sau

1. It would be better if you go to his house. 

=) went

2. If she followed my advice, she would be richer now. 

=) (Câu này không có lỗi sai)

3. If you have any trouble, will call him. 

=) I

4. If you will help me, it would be easier. 

=) helped

5. I think be very happy if you came to my house.

=) bỏ

 6. If I am a bird, I could fly

=) were

 7. If the goalkeeper didn’t catch the ball, they lose.

=)  lost

 8. If Jane didn’t love her, he hadn’t have married her.

=) wouldn't

 9. That plant dies if you don’t water it. 

=) will die

10. If not you work hard, you can’t pass the exam.

=) you don't 

đâu giúp gì???

Bn xem lại đề nha !

The big book is .......... .

\(\Rightarrow\)The big book is mine

Hok tốt

The big book is .......... .

Select one: mineI

                   don't know

.                  mefor my

1. plays

2. go 

3. Will / collect 

4. to play 

5. going 

6. did 

7. are playing

8. do 

9. to play

10. have collected                                ~HT~

IV. Complete the sentences with the correct form or tense of the verb play, go, do or collect.

1. He plays tennis with his father every Sunday.

2. We will go camping in Dam Sen Park next Saturday.

3. Will you collect coins some day in the future?

4. Do you want to do a jigsaw puzzle with me?

5. I enjoy going cycling at the weekend.

6. My uncle did karate when he was young.

7. The children are playing volleyball on the beach at the moment.

8. When I’m waiting for the train, I usually do crosswords.

9. She diss playing chess because she finds it boring.

10. I have collected books since I was ten years old.

giúp vs

1. I enjoy playing sport because it's good for my health

2. Do your children go camping every summer holiday?

3. I think photography can be an expensive hobby

4. My cousin is going to give me a book as a gift next birthday. ( chỗ này dùng TLĐ cx ko sao )

5. He finds mountain climbing dangerous so he doesn't take it up

6. I hope in the future he will teach me how to do eggshell carving.

giúp vs

1. Susan's hobbies are reading and gardening

2. She started reading when she was 4 years old

3. she felt interested

4. Because it can make her relaxed and calm.( mình nghĩ chỗ này có thể viết thêm vế sau, đổi ngôi + chia thì đi )

5. she has planted vegetables- carrots,potatoes,etc.

6. she waters plants in the evening.

giúp vs

VIII. Choose the word which best fits each gap.

Many people (1) _______ crafting with paper. The materials are readily available and don’t cost much; and no super special talents is needed. Anyone (2) _______ be a paper crafter.

There are many different paper craft techniques. Origami is one of ancient techniques developed in Japan where squares of paper are (3) _______ and formed into various objects such as flowers, animals, and boxes. Card (4) _______ is also a favourite paper craft technique. Birthday cards are the most popular greeting cards, followed by Christmas cards. Receiving a (5) _______ card is a special gift, because of the time and effort someone spent making it. It lets the recipient know just how much you care (8) _______ them.

1.   a. enjoy                      b. decide                    c. want                        d. learn

2.   a. must                        b. should                    c. can                          d.will

3.   a. wrapped                 b. folded                    c. torn                         d.taken

4.   a. making                   b. doing                      c. changing                d. receiving

5.   a. handmake              b. handmaking          c. handmade              d. making hand

6.   a. in                             b. on                           c. over                        d. about