甲乙两个工厂的平均技术人员比例为45%，其中甲厂的人数比乙厂多12.5%，技术人员的人数比乙厂的多25%，非技术人员人数比乙厂多6人。甲乙两厂共有多少人？（）
A.680
B.840
C.960
D.1020
参考答案：A
解析：和差倍比问题解析由题干中"甲厂人数比乙厂多12.5%"可知甲、乙两厂总人数之比为9：8，则可假设甲厂总人数有9n，乙厂总人数有8n，甲乙总人数为17n，故总人数一定能被17整除，排除选项B、C；在A和D之间选择，直接代入A选项，则有680=17n，n=40，则甲厂共360人，乙厂共320人，两厂的技术人员总数为680×45%=306人，甲厂技术人员有170人，非技术人员为190人，乙厂有技术人员136人，非技术人员184人，甲乙两厂的非技术人员相差190-184=6人，满足题意，验证成立。故正确答案为A。标签直接代入数字特性
| 阅读下面短文，并做短文后面的题目，从四个选项上中，选出最佳答案。 |
| New rules and behaviour standards (行为规范) for middle school students came out in March. Middle school is going to use a new way to decide who the top students are. The best students won't only have high marks. They will also be kids who don't dye (染) their hair, smoke or drink. The following are some of the new rules. Tell the truth. Have you ever copied someone else's work on an exam? Don't do it again! That's not something an honest student should do. If you have played computer games for two hours in your room, don't tell your parents you have done homework. Do more at school. Good students love animals and care for other people. April is Bird-Loving Month in our country. Is your school doing anything to celebrate? You should join! That way, you can learn more about animals and how to protect them. When more people work together, it makes it more fun for everyone. Have you ever quarreled with your teammates when your basketball team lost? Only working together can make your team stronger. Be friendly to the people you are with. Try to think of others, not only yourself. Be open to new ideas. Have you ever thought that people could live on the moon? Perhaps you'll discover Earth II someday. Don't look down on new ideas. Everyone's ideas are important. You should welcome them, because new ideas make life better for everyone. Protect yourself. Has someone ever taken money from one of your classmates? Don't let it happen to you. If you have to go home late, you should let your parents know. Use the Internet carefully. The Internet can be very useful for your studies. But some things on the Internet aren't for kids, so try to look at Web pages that are good for you. You can use the Web for fun or homework. Can't you find any good Web sites for children? Here are some: http ://kids. eastday. com http ://www. chinakids. net. com http: //www. cycnet. com |
| 1. The school new rules will help kids by telling them ___. |
[ ] |
| A. how they can study well B. what they should do at school C. what is right and what is wrong D. how they can protect themselves |
| 2. According to the passage, which of the following is not true? |
[ ] |
| A. Take care of yourself when you are out. B. Tell the truth, even when you are wrong. C. Keep some animals to protect them. D. Use the Internet, but keep away from bad things. |
| 3. The main idea of the fourth paragraph is about ___. |
[ ] |
| A. making the team stronger B. working together with others C. being a good friend to others D. getting on well with others |
| 4. Good Web sites for children can ___. |
[ ] |
| A. be a waste of time B. help them with their studies C. do homework for them D. make life easier |
| 5. The passage tells us how to ___. |
[ ] |
| A. be top students B. do more at school C. care for others D. use the Internet |