Gọi số học sinh khối 6 là a ( a

N* ) 

Vì số học sinh lớp 6a bằng 

số học sinh khối 6 nên số học sinh lớp 6a là:  

. a 

Vì số học sinh lớp 6b  bằng 

số học sinh khối 6 nên số học sinh lớp 6b là : 

. a 

Mà a là số học sinh khối 6 nên a bằng số học sinh của 3 lớp 6a , 6b , 6c cộng lại 

=>  

. a + 

. a +48 = a

=>   

. a + 

. a +48  - a = 0

=>  a (

) + 48  = 0 

=> a ( 

) + 48 = 0

c. Bắt đầu từ lớp 1 năm 2020, lớp 6 năm 2021, lớp 10 năm 2022

Số HS lớp 6A là :

120 : ( 2 + 1 ) = 40 học sinh

Số HS lớp 6B và 6C là :

120 - 40 = 80 học sinh

Số HS lớp 6B là :

( 80 + 6 ) : 2 = 43 học sinh

Số HS lớp 6C là :

43 - 6 = 37 học sinh

Đáp số : ...............

quy đồng 1/5=10/50;4/25=8/50

tổng số phần của lớp 6/1;6/2;6/3;6/4 là

10/50+8/50+11/50+12/50=41/50

vậy lớp 6/5 chiếm số phần là

50-41=9 phần

học sinh lớp 6/5 là

250/50*9=45 học sinh

                  đáp số:45 học sinh

Số học sinh lớp 6A = 9/25 tổng số học sinh 3 lớp còn lại => số học sinh lớp 6A = 9/(9 + 25) = 9/34 tổng số hoc sinh 4 lớp. Tương tự thì số học sinh lớp 6B, 6C tương ứng bằng 21/85 và 4/17 số học sinh cả 4 lớp. => Phân số chỉ số học sinh lớp 6D so với số học sinh cả 4 lớp là 1 - (9/34 + 21/85 + 4/17) = 43/170 (số học sinh). => Số học sinh cả 4 lớp là 43 : 43/170 = 170 (học sinh) => Số học sinh lớp 4A là: 170 x 9/34 = 45 (học sinh). Số học sinh lớp 4B là: 170 x 21/85 = 42 (học sinh). Số học sinh lớp 4C là: 170 x 4/17 = 40 (học sinh)

1. We usually_______breakfast at 7.15 a.m . * 0/5 go watch have get up 2. I always______my face in the morning. * 0/5 watch wash brush help 3. We______lunch at school at 12 p.m . * 0/5 help go relax have 4. After school, I_________in the library. * 0/5 study brush do get up 5. I________video games with my friends. * 0/5 get wash play go 6. We often sit on the sofa and________videos. * 0/5 relax help wash watch 7. I _________my teeth before bed. * 0/5 wash brush have go 8. Indicate the word whose it differs from the other three in pronunciation: mother - your - four - forty * 0/5 forty your mother four 9. Indicate the word whose it differs from the other three in pronunciation: there - these - thank - those * 0/5 these there those thank 10. town / Hội An / old / is / Town / an / . / * 0/5 Town Hội An is town old. Hội An Town is an old town Town Hội An is an old town. Hội An Town is an old town. 11. population / got / 152,160 / It / about / of / a / has / . / * 0/5 It has got 152,160 population of a about. It has got about a population of 152,160. It has got about 152,160 of a population. It has got a population of about 152,160. 12. Việt Nam / in / It / south / is / the / centre / of / . / * 0/5 It is in the centre south of Việt Nam. It is in the south centre of Việt Nam It is in Việt Nam of the centre south. It is in the south centre of Việt Nam. 13. It’s ______________ here than in my country. * 5/5 expensive more expensive most expensive the most expensive 14. Why is this class _________ than the other class? * ··· /5 quiet more quiet most quiet quieter 15. Are the buildings in New York ______________ than the buildings in Oxford? * ··· /5 modern moderner most modern more modern 16. This house is ___________ than that house. * 0/5 more pretty pretty prettier most pretty 17. _____________people are there in the house? * 5/5 How many How much What Who 18. There are________passengers on the ship. * 0/5 6.036 6.063 6.630 6.360 19. There are__________real trees on the ship. * 0/5 20 50 40 30 20. The name of this book________Friends Plus. * 5/5 are be is am

1. We usually_______breakfast at 7.15 a.m . * 0/5 go watch have get up 2. I always______my face in the morning. * 0/5 watch wash brush help 3. We______lunch at school at 12 p.m . * 0/5 help go relax have 4. After school, I_________in the library. * 0/5 study brush do get up 5. I________video games with my friends. * 0/5 get wash play go 6. We often sit on the sofa and________videos. * 0/5 relax help wash watch 7. I _________my teeth before bed. * 0/5 wash brush have go 8. Indicate the word whose it differs from the other three in pronunciation: mother - your - four - forty * 0/5 forty your mother four 9. Indicate the word whose it differs from the other three in pronunciation: there - these - thank - those * 0/5 these there those thank 10. town / Hội An / old / is / Town / an / . / * 0/5 Town Hội An is town old. Hội An Town is an old town Town Hội An is an old town. Hội An Town is an old town. 11. population / got / 152,160 / It / about / of / a / has / . / * 0/5 It has got 152,160 population of a about. It has got about a population of 152,160. It has got about 152,160 of a population. It has got a population of about 152,160. 12. Việt Nam / in / It / south / is / the / centre / of / . / * 0/5 It is in the centre south of Việt Nam. It is in the south centre of Việt Nam It is in Việt Nam of the centre south. It is in the south centre of Việt Nam. 13. It’s ______________ here than in my country. * 5/5 expensive more expensive most expensive the most expensive 14. Why is this class _________ than the other class? * ··· /5 quiet more quiet most quiet quieter 15. Are the buildings in New York ______________ than the buildings in Oxford? * ··· /5 modern moderner most modern more modern 16. This house is ___________ than that house. * 0/5 more pretty pretty prettier most pretty 17. _____________people are there in the house? * 5/5 How many How much What Who 18. There are________passengers on the ship. * 0/5 6.036 6.063 6.630 6.360 19. There are__________real trees on the ship. * 0/5 20 50 40 30 20. The name of this book________Friends Plus. * 5/5 are be is am

1. We usually_______breakfast at 7.15 a.m . * 0/5 go watch have get up 2. I always______my face in the morning. * 0/5 watch wash brush help 3. We______lunch at school at 12 p.m . * 0/5 help go relax have 4. After school, I_________in the library. * 0/5 study brush do get up 5. I________video games with my friends. * 0/5 get wash play go 6. We often sit on the sofa and________videos. * 0/5 relax help wash watch 7. I _________my teeth before bed. * 0/5 wash brush have go 8. Indicate the word whose it differs from the other three in pronunciation: mother - your - four - forty * 0/5 forty your mother four 9. Indicate the word whose it differs from the other three in pronunciation: there - these - thank - those * 0/5 these there those thank 10. town / Hội An / old / is / Town / an / . / * 0/5 Town Hội An is town old. Hội An Town is an old town Town Hội An is an old town. Hội An Town is an old town. 11. population / got / 152,160 / It / about / of / a / has / . / * 0/5 It has got 152,160 population of a about. It has got about a population of 152,160. It has got about 152,160 of a population. It has got a population of about 152,160. 12. Việt Nam / in / It / south / is / the / centre / of / . / * 0/5 It is in the centre south of Việt Nam. It is in the south centre of Việt Nam It is in Việt Nam of the centre south. It is in the south centre of Việt Nam. 13. It’s ______________ here than in my country. * 5/5 expensive more expensive most expensive the most expensive 14. Why is this class _________ than the other class? * ··· /5 quiet more quiet most quiet quieter 15. Are the buildings in New York ______________ than the buildings in Oxford? * ··· /5 modern moderner most modern more modern 16. This house is ___________ than that house. * 0/5 more pretty pretty prettier most pretty 17. _____________people are there in the house? * 5/5 How many How much What Who 18. There are________passengers on the ship. * 0/5 6.036 6.063 6.630 6.360 19. There are__________real trees on the ship. * 0/5 20 50 40 30 20. The name of this book________Friends Plus. * 5/5 are be is am