Tìm các tỉ số bằng nhau trong các tỉ số sau đây rồi lập các tỉ lệ thức: 28:14; 212:2; 8:4; 12:23; 3:10; 2,1:7; 3:0,3.

Các câu hỏi liên quan

1. I enjoy _____ alone. A. be B. being C. to be D. been 2. Would you like _____ to the party ? A. to come B. come C. coming D. came 3. Do you mind _____ such a long way to work every day ? A. to travel B. travel C. to have travelled D. travelling 4. Please remember ______ this letter. A. to post B. post C. posting D. posted 5. Jane needed some money. She tried ____ Harry but he couldn’t help her. A. to have asked B. ask C. to ask D. asking 6. He tried _____ the shelf but he wasn’t tall enough. A. reach B. reaching C. to reach D. reached 7. We stopped _____ hello to her. A. say B. saying C. to have said D. to say 8. I’ll invite her _____ my daughter. A. teaching B. teach C. to teach D. taught 9. I don’t feel like _____ to the cinema now. A. go B. going C. to go D. gone 10. Tourists are not allowed ______ in the Temple. A. to talk B. talk C. talking D. talked 11. The teacher doesn’t allow _____ dictionaries in the final examination. A. being used B. use C. using D. to use 12. Many countries have considered _____ the victims of the tsunami. A. to have helped B. to help C. help D. helping 13. Vietnam failed _____ Tiger Cup 2004 ! A. to have won B. win C. to win D. winning 14. Suddenly everybody stopped _____. There was silence. A. talking B. to talk C. talk D. talked 15. He tried to avoid _____ my question. A. answer B. answering C. to answer D. answered 16. Paula has given up _____ to lose weight. A. try B. trying C. to try D. have tried 17. We decided ______ at home. A. to stay B. stay C. staying D. stayed 18. I don’t advise anybody ______ in that hotel. A. stay B. to stay C. staying D. stayed 19. The mother made her child ______ the word. A. repeat B. to repeat C. repeating D. repeated 20. My parents don’t let me ______ out alone. A. go B. to go C. going D. to be going 21. I cannot remember ______ him last week. A. meet B. meeting C. to meet D. met 22. I’ll go with you when I’ve finished ____ my homework. A. to have done B. to do C. doing D. do 23. The teacher makes us ______ around the school yard five times before the PE lessons. A. run B. to run C. running D. ran 24. Danny promised ______ his sister a new doll as a birthday present. A. buy B. to buy C. to buying D. buying 25. The monitor of my class suggested ______ to the cinema after the meeting. A. go B. to go C. to going D. going