一项工程,甲单独做a天完成,乙单独做b天完成.(1)甲的工作效率为______,

题型:填空题

问题:

一项工程,甲单独做a天完成,乙单独做b天完成.
(1)甲的工作效率为______,乙的工作效率为______.
(2)现在甲、乙合作8天完成了这项工程,则可以列出等式为______.
(3)若甲先单独工作5天后,甲、乙又合作3天完成了这项工程,则可以列出等式为______.
(4)若甲先单独工作5天后,乙又单独工作2天,最后甲、乙合作2天终于完成了全部工程,则可以列出等式为______.
(5)若甲、乙合作m天完成了整个工程的-半,则可列等式为______.
(6)若乙单独工作c天,又与甲合作m天完成了整个工程的
1
3
,则可列等式为______.
由以上各题可以总结出:工程问题中列方程用到的相等关系-般来说都是从工作量、工作效率、工作时间这三个量中的哪个量来找?______.
考点:一元一次方程的应用
题型:填空题

阅读理解。

     Long ago, there was an interesting man called Effendi (阿凡提), He was very humorous. One day

he had a joke with the Prime Minister (宰相). He said that the Minister would die the next day. Really

the next day, the Minister fell off the horse and died. When the king learned this, he got angry and sent

his men to catch Effendi at once. When Effendi was in front of the King, the king shouted angrily, “Effendi, since (既然) you know when my Minister would die, you must know the date of your own death. Say it

out, or you will die today.” Effendi looked at the king for a while, he answered, “But how can I know?

I’ll die two days earlier than you.” Because the king was afraid if he killed Effendi, he himself would die

after that. He thought he must keep Effendi alive as long as he could, so he let Effendi go.

1. The story tells us _______

A. how Effendi fooled the king  

B. when the king would die

C. why the Minister died  

D. Effendi knew the dates of everyone’s death

2. The Prime Minister died because _______

A. Effendi killed him

B. Effendi said he would die

C. he was badly ill

D. he fell to the ground from the horse

3. Why did the king ask Effendi to tell him the date of his own death?

A. In this way the king would know when he would die

B. He wanted to find an excuse to kill Effendi

C. He himself had known the date of Effendi’s death

D. He wanted to know when Effendi would die

4. The king let Effendi go because _______

A. he hoped to live a long life

B. he was afraid of Effendi

C. he didn’t believe Effendi’s words

D. he knew he would die two days later

5. Which of the following is not true?

A.The Minister died after the day when Effendi played a joke on him.

B. The king was afraid of death

C. Effendi didn’t know when the king would die

D. If the king killed Effendi, he himself would die two days later.

题型:填空题

三角形的面积是平行四边形的面积的[ ]

A.2倍

B.一半

C.3倍

D.无法确定

题型:填空题

——Your coffee smells great!

——It’s from Mexico. Would you like ____  ?

A.it

B.some

C.this

D.little

题型:填空题

假定小王于2013年6月在银行以定期方式存入10000元,存期1年,当时年利率为3.5%,通货膨胀率为2.5%,如果2014年一年期存款利率调整为1.5%,通货膨胀率为5.0%,则小王这笔定期存款的实际收益率是

A.-1.42%

B.0.56%

C.-0.76%

D.-1.50%

题型:填空题

世界年产量95%以上的H2O2由蒽醌氧化法生产。反应过程如下:

下列说法不正确的是(   )

A.H2O2可用作漂白剂、消毒剂,也可作为火箭燃料

B.H2O2可使湿润的KI淀粉试纸变蓝

C.蒽醌氧化法生产H2O2的实际结果是H2和O2生成H2O2

D.H2O2化学性质稳定,便于储存和运输

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