试题与答案

一架飞机在两城之间飞行,风速为24千米 /小时 ,顺风飞行需2小时50分,逆风飞

题型:解答题

题目:

一架飞机在两城之间飞行,风速为24千米 /小时 ,顺风飞行需2小时50分,逆风飞行需要3小时。求无风时飞机的飞行速度和两城之间的航程。(6分)

答案:

飞机的航速为840千米/小时,两城之间的航程2448千米

题目分析:设无风时飞机的航速为x千米/小时,

根据题意,列出方程得(x+24)×= (x-24)×3,解这个方程,得x=840,

航程为(x-24)×3="2" 448(千米)

点评:本题最关键之处在于无风时的速度与顺风时和逆风时速度的关系,再者,由于无论顺风还是逆风速度,总的航程都不会改变,由此可以列出这道方程式。

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题型:阅读理解

Daredevil climber Alain Robert, known as the French Spiderman, stood strong winds and rain to climb the world's tallest skyscraper, Taipei 101, Saturday.

Robert, dressed in red rain jacket, tights and climbing shoes, climbed up ropes hung down the side of the 101 storey, 1,667-foot office tower, reaching the top in around four hours."It was a very big moment and I felt a lot of satisfaction though I was so tired and nearly all of my muscles were painful.I felt completely eased." said Robert after taking the ride down in one of the tower's lifts, the world's fastest.

Several hundred on-lookers and shoppers gathered at the base of the tower watching and cheering Robert's progress through live pictures on a large television screen.At times he disappeared from view as clouds passed by the top of the tower surrounding the upper stories.

The 42-year-old Frenchman has covered scores of well-known structures around the world including the Empire State Building and the Eiffel Tower——without permission or any safety equipment or ropes.

This time Robert was wearing a harness (背带) fastened to safety ropes for the entire climb.He used the ropes to pull himself up most of the way, using his hands and feet to climb up the walls for only short sections.He said that the management had requested he wear the ropes and safety equipment, which had also become necessary due to the rain making the windows and frames very slippery.Robert said he would not carry his pity the next time.

小题1:The text mainly tells us that _________.

A.another world record was broken by a Frenchman

B.The French Spiderman climbed the world's tallest building

C.How Alain Robert got the name" Daredevil"

D.Alain Robert was praised for his great success小题2:During his climbing up Taipei 101, Alain Robert ________.

A.never felt tired all the time

B.never used his hands and feet

C.stayed somewhere for a short rest

D.was not seen on the television screen now and then小题3:When Alain Robert climbed the Empire State Building, he was likely to ________.

A.use only his hands and feet

B.be 42 years old

C.carry some safety equipment

D.get permission of someone小题4:According to the text, we can infer that Alain Robert ________.

A.spent three hours climbing Taipei 101

B.chose a rainy day on purpose

C.will climb Taipei 101 a second time

D.got lots of help from on-lookers

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