并说出为什么 最好和分数有关 英语也要解答

并说出为什么 最好和分数有关 英语也要解答
并说出为什么
最好和分数有关 英语也要解答

并说出为什么 最好和分数有关 英语也要解答
（1）有一台电器,原价180元,后来降价销售,结果买的人增加了一倍,收入是原收入的3/2.这台电器降价多少元?
这道题可以用假设法
假设原来有1人购买,那么现在有1×（1+1）=2（人）
现在利润是原来的：3÷2=1.5
如果买的人数是原来的两倍,那么利润也应该是2倍,可是现在只有1.5倍,就差在降价上.
所以1.5÷2=3/4,现在价钱是原来的3/4.
降价：180×（1- 3/4）=45(元)
（2）有3个容积相等的瓶子装满了溶液,纯酒精与水的比分别是2:1、3:2、4:1.把3瓶酒精溶液混合后,纯酒精与水的比是多少?
∵容积相同,并全部灌满,所以分数也应一样.
先列个表
①瓶 ②瓶 ③瓶
纯酒精 2 3 4
水 1 2 1
总量 3 5 5
总数份数不一样,因此要统一.
①瓶 ②瓶 ③瓶
纯酒精 2（10） 3 （9 ） 4（12）
水 1（5 ） 2 （6 ） 1（3 ）
总量 3（15） 5 （15） 5（15）
纯酒精：水——（10+9+12）：（5+6+3）=31:14
（3）有一批书,印刷厂要把它们分包运走到书店（每包数量相同）.第一次他们运来了11/18,包了14包余40本.第二次他们把剩下的全运来了,和第一次剩下的40本一起包了10包.这批书共多少本?
第一次包14个余40个,和第二次剩下的一起包10个,所以全部书能包：
14+10=24（包）
第一种方法：
一个包占总数的1/24.那么14包占1/24×14=7/12.
40本就对应11/18-7/12=1/36.
40×36=1440（本）←——————总数
第二种方法：
第一次运了11/18,那么就是24×11/18=44/3（包）
40本对应的就是44/3-14=2/3.
40÷2/3=60（本）←——————1包的数量
60×24=1440（本）

（4）某大学300名学生报名加入了“奥运会服务自愿者”行列,后来又有13名同学报名加入了这个行列,这样男同学人数增加了1/25,女同学人数增加了1/20.现在这个学校报名加入这个行列的男、女学生各有多少人?
设原男x人,原女（300-x）人.
（1+4％）x + （1+5％）×（300-x）= 300 + 13
x = 200
现男：200×(1+4％)=208(人)
现女：300-200=100（人）
100×（1+5％）=105（人）
或
208-200=8（人）
13-8+100=105（人）
这些都是我收藏的好题
英语嘛.
Car One is running ________(two)faster than Car Two.
Tom drove at 50 miles an hour and Jim drove at 100 miles an hour.( 改为同义句）
Jim drove _______ ________ than Tom.
首字母填空
An earthquake may hit some places at any time. Do you know w_______to do in an earthquake? Please let me tell you.
D______an earthquake, if you are outside , you must get into the open air and stay away from buildings, trees and other dangerous things. If you are i_______, you must stand in a corner, or get under a heavy desk or a t________. If you drive a car, or a bus, you must drive to the side of the road and stop.
After an earthquake , you must check everyone in your family, and see w________gas, water, and electric lines are OK. Please don’t strike matches or make a fire. A gas line may b________ broken. You must keep the telephone lines clear. Don’t u________ your phone or drive your car u___________ the earthquake is over.
阅读理解
（一）
Ali,who was working a long way from home wanted to send a letter to his wife, but he could neither read nor write, and he had to work all day, so he could only look for somebody to write his letter late at night .At last he found the house of a letter writer whose name was nasreddin.
nasreddin was already in bed. It is late, he said. What do you want? I want you to write a letter to my wife , said Ali , nasreddin was not pleased. He thought for a few seconds and then said, Has the letter got to go far? What does that matter? Answered Ali.
Well, my writing is so strange that only I can read it, and if I have to travel a long way to read your letter to your wife, it will cost you a lot of money. Ali went away quickly. Multiple choice.
( ) 1. Ali wanted to ____to his wife.
A. get something B. have a letter written
C. bring a flower D. say good-bye
( ) 2. At last he found the house of_____.
A. a writer B. a seller C. an old man D. a letter-writer
( ) 3.When Ali told what he wanted to do Nasreddin was______.
A. not pleased B. pleased C. excited D. angry
( ) 4.Nasreddin said that his writing was_____.
A. easy for anyone to read B. strange for anyone to read
C. too strange for anyone to write D. difficult for anyone to read
( ) 5. This story tells us______.
A. not to ask anybody for help B. not to trouble others at night
C. not to ask for help without money D. not to trust others
（二）
An old man died and left his son a lot of money. But the son was a foolish young man,and he quickly spent all the money, so that soon hehad nothing left.Of course ,when that happened, all his friends lefthim.When he was quite poor and alone, he went to see Nasreddin, who was a kind, clever old man and often helped people when they had troubles.
My money has finished and my friends have gone,said the young man. What will happen to me now?
Don't worry , young man,answered Nasreddin.Everything will soon be all right again. Wait ,and you will soon feel much happier.
The young man was very glad.Am I going to get rich again then? heasked Nasreddin.
No, I didn't mean that, said the old man.I meant that you would soon get used to being poor and to having no friends.
( ) 1. An old man died and left his son_______.
A. nothing B. some gold C. much money D. only a house
( ) 2. When the son was________, he went to see Nasreddin.
A. short of money B. quite poor and sick
C. in trouble D. quite poor and alone
( ) 3.The young man was very glad because Nasreddin said that________.
A. he would become rich again B. he would soon feel much happier
C. he would become clever D. he would have more friends
( ) 4.Nasreddin meant the young man______.
A. would get rich again B. would get used to having nothing
C. would get used to being in trouble D. would get out of poorness
( ) 5.What this story tells us is________.
A. that money is everything B. that money makes the mare go
C. to save each penny D. that misfortune tests the sincerity of friends