有一水池 只打开甲水龙头要24分钟注满,只打开乙要36分钟注满,现在先打开甲水龙头几分钟,然后关掉甲,再打开乙注满,已知乙水龙头比甲水龙头多开26分钟,问注满水池共用几分钟?

有一水池 只打开甲水龙头要24分钟注满,只打开乙要36分钟注满,现在先打开甲水龙头几分钟,然后关掉甲,再打开乙注满,已知乙水龙头比甲水龙头多开26分钟,问注满水池共用几分钟?
有一水池 只打开甲水龙头要24分钟注满,只打开乙要36分钟注满,现在先打开甲水龙头几分钟,然后关掉甲,再打开乙注满,已知乙水龙头比甲水龙头多开26分钟,问注满水池共用几分钟?

有一水池 只打开甲水龙头要24分钟注满,只打开乙要36分钟注满,现在先打开甲水龙头几分钟,然后关掉甲,再打开乙注满,已知乙水龙头比甲水龙头多开26分钟,问注满水池共用几分钟?
因为甲水龙头每分钟注入水池1/24,乙水龙头每分钟注入水池1/36
设甲开了x分钟,则乙开了（x+26）分钟
故(1/24)x+(1/36)(x+26)=1
解得x=4
共要x+（x+26）=34分钟

设甲x分钟，乙y分钟，则有y-x=26，且x/24+y/36=1，解得x=4,y=30

34分钟，
甲开了4分钟，共注入了1/6，
乙开了30分钟，共注入了5/6.

不会，我最忌讳这样的题！

34分钟

总时间为34
设总容量为x 甲的时间为t则乙的时间为（t+26） 则甲的速度为x/24 乙为x/36
(x/24)*t + (x/36)*(t+26) = x
x被消掉 只剩t = 4

27又4/9

第二部分 语言知识运用（共三节，满分35分）
第一节 单项选择（共15小题，每小题1分，计15分）
( ) 16. Jacky Chan is very busy, so he goes to the movies.
A. always B. usually C. hardly ever D. often
( ...

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第二部分 语言知识运用（共三节，满分35分）
第一节 单项选择（共15小题，每小题1分，计15分）
( ) 16. Jacky Chan is very busy, so he goes to the movies.
A. always B. usually C. hardly ever D. often
( ) 17. I’m very because I don’t like exercise.
A. healthy B. health C. unhealthy D. healthily
( ) 18. —I have a toothache. —You should .
A. drink a lot of water B. see a dentist
C. drink hot tea with honey D. listen to the music
( ) 19. —How long does it take you to watch English program every day?
—It me half an hour English program.
A. take, watch B. takes, watch C. takes, to watch D. take, to watch
( ) 20. — ? — I’m going with my friends.
A. What are you doing B. Where are you going
C. Who are you going with D. When are you going
( ) 21. I’m hungry. Could you buy for me?
A. some bread B. some breads C. some water D. some potato
( ) 22. Let’s enjoy the song “take me to your heart”. It sounds .
A. well B. sadly C. bad D. nice
( ) 23. I don’t like this CD. Can you show me one?
A. other B. the other C. another D. others
( ) 24. — did he hiccup? —For 5 months.
A. How long B. How many C. How much D. What time
( ) 25. —What did you do last night? —______.
A. I watch a TV program B. I have no idea
C. I did some housework D. I will read some books
( ) 26. She likes talking with others. But I often stay at home and read books. So I’m .
A. funnier B. calmer C. more outgoing D. wilder
( ) 27. — . —That’s a good idea.
A. I like fishing B. Let’s take a vacation
C. I agree D. I’m going to Wenzhou.
( ) 28. It’s my birthday. I’m going to .
A. have a party B. have a swim C. have a walk D. have a rest
( ) 29. The school is next to Mr Black’s home, so he usually goes to work .
A. by car B. by bike C. on foot D. by bus
( ) 30. —My mother was ill yesterday. — .
A. It isn’t good B. I’m sorry to hear that
C. I’m glad to hear that D. That’s all right
第二节情景交际(共10小题，每小题1分，计10分)
请从Ⅱ栏中找出与Ⅰ栏各句子相对应的答语
Ⅰ Ⅱ
( ) 31.Where did you go on vacation? A. Have a good time.
( ) 32.Did you buy anything? B. No, she is going to the park.
( ) 33.Where was your father born? C. Because I love math.
( ) 34.Why did you study engineering? D.I came by taxi.
( ) 35.Let’s travel all over the world. E. Sounds exciting.
( ) 36.Are we all going fishing? F. Yes, I bought some souvenirs.
( ) 37.How often do you have your English class? G. I visited two.
( ) 38.How many countries did you visit last year? H. I went to Hangzhou.
( ) 39.How did you come to this English class? I. In Wenzhou.
( ) 40.I’m going to London next week. J. Every day. So we’re very busy.
第三节 完形填空（共10小题，每小题1分，计10分）
Who is your idol(偶像)? Why do you like the person? Cool looks? Money? A lot of talent? Shanghai teenagers say they 41 them more than that. Most of them say their idols are hardworking and brave(勇敢).This summer, Shanghai’sXinwen Evening News 42 about 1,000 middle school students about their idols. The newspaper 43 people in six groups: leader, young heroes, teenagers, writers, artists and business people. Students were asked to 44 one from each group. NBA 45 Yao Ming was the No.1 Chinese idol 46 48 % of all votes(投票). Popular singer Jay Chou(周杰伦) is the teen’s most 47 star. A teenager said,”Jay is so kind to his mother and grandma. He 48 good care of them. Shanghai students also like US Bill Gates. More than half picked him as their idols. A junior student who likes Gates said: “Bill was not 49 rich. He worked hark. And he doesn’t like to tell everyone how rich he is. He also has courage(勇气). He 50 school to start his own business!”
( ) 41. A. hate B. dislike C. don’t like D. like
( ) 42. A. asked B. talked C. spoke D. told
( ) 43. A. get B. keep C. put D. play
( ) 44. A. pick B. pick up C. hope D. give
( ) 45. A. writer B. star C. businessman D. leader
( ) 46. A. in B. with C. by D. for
( ) 47. A. best B. funny C. favorite D. pleasant
( ) 48. A. takes B. looks C. pays D. draws
( ) 49. A. kept B. hoped C. born D. wanted
( ) 50. A. left B. came C. went to D. went out
第三部分 阅读理解 （共两节，满分25分）
第一节 阅读下列短文，从每题所给的A、B、C和D四个选出最佳选项。（共10小题，每小题2分，计20分）
A
One day, Bob looked sad. His mother asked him what the matter was. He said he had no one to play with. He wished they had stayed in New York City. He had friends there. But his mother said he would soon make friends there. Just then there was a tap on the door. Mrs Miller opened it. There stood a woman with red hair. She was Mrs Carey living next door. She came to ask for two eggs. She wanted to bake(烘烤) a cake. Mrs Miller asked Mrs Carey to have coffee and they talked happily.
That afternoon there was another tap on the door. Mrs Miller opened it. There stood a boy with red hair. His name was Tom Carey. He sent cake and two eggs to them. Mrs Miller asked him to come in and met Bob. Tom and Bob were about the same age. Soon they were having cake and milk. “Can you stay and play with me?” asked Bob. Tom said he can stay for an hour. Then they played ball. Bob’s dog Trix would like to get in the game, too. Tom found it was fun to play with the dog. He had no dog of his own.
Bob was glad Tom lived next door. Now he had someone to play with. “I’m glad your mother needed two eggs” Bob said to Tom. Tom laughed. He said his mother didn’t really need the eggs. She just wanted to make friends with Bob’s mother!” Then Bob laughed, too.“That’s a funny way to make friends,”he said,“But it is a nice way. It worked!”
( ) 51. Mrs Carey came to Mrs Miller’s house in order to _________.
A. borrow two eggs B. send a cake
C. play with Trix D. make friends with Mrs Miller
( ) 52. Mrs Miller was_________at Mrs Carey’s visit.
A. glad B. surprised C. unhappy D. worried
( ) 53. Trix was the name of_________ .
A. Tom’s toy B. a dog
C. Mrs Carey’s daughter D. Mrs Miller’s son
( ) 54. In the sentence “Just then there was a tap on the door.”， the word“tap”means
“_________”.
A. a push B. a voice C. a light knock D. a noise
( ) 55. Which of the following is Not true?
A. Tom had a dog.
B. Bob had friends in New York City.
C. Tom and Bob were about the same age.
D. Tom lived next door to Bob.
B
In 1969， two American astronauts(宇航员) landed on the moon for the first time in history. They stayed there for 21 hours before coming back to the earth. On December 4，NASA (美国宇航局) said they would send people to the moon again. But this time astronauts will build a moon base(基地) and stay there forever.
NASA said they would build the moon base to get ready for(准备好) a trip to Mars(火星). A base on the moon will help people travel farther in space. The big plan will take 16 years to complete(完成). Astronauts will fly to the moon and land in 2020. The moon base will be ready by 2024. NASA said the moon base would be probably at one of the moon’s poles (极点). There is always sunlight there. That’s good for solar power. There could also be minerals (矿物) and even water.
In 2020， two spaceships will fly to the moon with four astronauts and six tons(吨) of building materials(建筑材料). The four astronauts will start to work on the base. They will come back after a week. Then another four astronauts will arrive and keep on building. Each four-member group will stay for only one week at a time.
Once the base is ready for use，astronauts will stay for up to 180 days at a time. In 2024， astronauts should be able to stay as long as they want in the base.
The plan will cost hundreds of billion(十亿) of US dollars. But NASA won’t do it alone. Japan、Russia and other European countries will join. China may also join.
( ) 56. Which country landed on the moon with person?
A. China B.America C.Australia D.Japan
( ) 57.Why will NASA build the moon base?
A. Because they want to get ready for the trip to Mars.
B. Because they want to travel farther in space.
C. Because they want Americans to live on the moon.
D. Both A and B.
( ) 58.Astronauts will work on the moon for ______ years to complete the moon base.
A. four B. twelve C. sixteen D. twenty
( ) 59.The moon base will be probably at one of the moon’s poles for ______.
A. sunlight B. minerals C. water D. A， B and C
( ) 60. Which country may not join the plan?
A. Japan. B. India. C. America. D. China.
第二节 任务型阅读（共5小题，每小题1分，计5分）
下面是一位妇女遭抢劫后与一位警察的对话。请阅读对话，然后完成后面的案情记录.(每空限一词)
Woman: Good morning, sir. Could you help me, please?
Policeman: Certainly. What can I do for you?
Woman: Someone has robbed me of my wallet钱包).
Policeman: What’s inside?
Woman: 30,000 yuan and my ID card.
Policeman: When did this happen?
Woman: An hour ago, I was riding home on my bike with the money I just
took from the bank. Suddenly a man on a black car came near and grabbed my wallet and rode away.
Policeman: Do you remember the robber, madam?
Woman: Yes. He is thin but tall about 1.75m. He has a square face with a big
nose and short black hair. He was wearing a pair of sunglasses and he’s about 30 years old.
Policeman: Anything else？
Woman: Nothing.
Policeman: Your name, please?
Woman: Jane Brown.
Policeman: Ok, Mrs Brown. We’ll let you know as soon as we catch the robber.
A robbery（抢劫）record
No.015
Time
9:00a.m.June13,2007
Place
On the way home from the 61

About the robber
Age: about 62 Height: about 1.75m.
Face: square Nose: 63
Eyes：with a pair of glasses.
Hair: 64

The whole story
The man on his 65 car robbed Jane Brown of her wallet with 30,000 yuan inside.

Reported by Jane Brown
Recorded by Jack Smith , June 13,2007


第四部分 写（共两节，满分20分）
第一节 单词拼写（共10小题，每小题1分，共计10分）
根据所给中文，写出下列句子空缺处各单词的正确形式（每空限填一词）
66.I’m very (口渴的)after running.
67.We see with eyes and hear with our (耳朵).
68.The funny boy often makes his classmates (发笑).
69.I’m not (感觉) very well.
70. My friend is the same as me. We are (都)quiet.
71. She is tired. She should go to bed （早）tonight.
72. I （需要）bananas to make milk shake.
73. She (成为) a movie star when she was three years old.
74.He is going to be an engineer when he (长大) up.
75.I think the Great Hall of the people has the most (舒服) seats.
第二节 书面表达（计10分）
丰富多彩的寒假生活即将开始了，快约上几个好朋友一起去旅行吧！假设你是马琳,请你通过e-mail的方式向你的朋友张鹏发出邀请,要他跟你一块出去旅行。
内容提示:
1. 向张鹏发出邀请;
2. 你的旅行计划包括活动内容、目的、时间、地点等;
3. 提醒他准备路途中需要的东西;
4. 约定出发时间和见面地点;
5. 词数:80左右;
6. 开头和结尾已给出,不计入总词数;
Dear Zhang Peng,
I hope all is going well……




Hope to see you soon!
Sincerely yours,
Ma Lin

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注满水池就像是一项工程，看作单位1，则甲和乙的速率分别为1/24和1/36。设联合注水时甲开了x分钟，乙就开了x+26分钟，水池被注满。列出方程：1/24*x+1/36*(x+26)=1，解得x=4，即甲开了4分钟乙开了30分钟将水池注满。

用方程解很简单，大家考虑一下不用方程，逻辑推理。
答案补充：设水池装水量为单位1，已知乙水龙头比甲水龙头多开26分钟，所以乙水龙头26分钟内会注满水池的26／36，所以水池中1-26／36=10／36的水由甲乙完成，根据题意剩下的这些水是甲乙各装了相同的时间把水池装满，所以甲乙用的时间是t=(10／36)÷(1／24+1／36)=4 所以甲用了4分钟，而乙再加上比甲多用的26分钟乙总共注...

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用方程解很简单，大家考虑一下不用方程，逻辑推理。
答案补充：设水池装水量为单位1，已知乙水龙头比甲水龙头多开26分钟，所以乙水龙头26分钟内会注满水池的26／36，所以水池中1-26／36=10／36的水由甲乙完成，根据题意剩下的这些水是甲乙各装了相同的时间把水池装满，所以甲乙用的时间是t=(10／36)÷(1／24+1／36)=4 所以甲用了4分钟，而乙再加上比甲多用的26分钟乙总共注水30分，最终甲乙共用时34分钟。
如果小学生这么思考，有助于提高逻辑推理能力。

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设：打开甲X分钟
X/24+（X+26）/36=1
X/24+X/36+13/18=1
5X+52=72
X=4
4+（4+26）=34（分）

甲每分钟灌池的24分之1，乙是36分之1，甲乙一起是5分之72.1-26分之36=10分之36，10分之36除以5分之72=4，4乘以2+26=34.答案是34