问题 问答题

为了加强市民的节水意识,合理利用水资源,某市采用价格调控手段以达到节水的目的.该市自来水收费价格价目表如下表所示:

(1)居民甲2月份用水12.5 m3,则应收水费()元;

(2)居民乙3、4月份共用水15m3(4月份用水量超过3月份),共交水费44元,求这户居民3、4月份的用水量.

答案

参考答案:

(1)12.5m3的水分三个收费段来收费,6×2+(10-6)×4+(12.5-10)×8=48(元).

(2)设3月份的用水量为xm3,则4月份用水量为(15-x)m3

∵4月份用水量超过3月份,∴15-x>x,即x<7.5.

①当x≤5时,15-x≥10,则有:

2x+2×6+4×(10-6)+8×(15-x-6-4)=44,

解得:x=4.

②当5<x≤6时,9≤15-x<10,则有:

2x+2×6+4×(15-x-6)=44,x-2,前后矛盾,舍去.

③当6<x<7.5时,7.5<15-x<9,则有:

2×6+4×(x-6)+2×6+4×(15-x-6)=44,方程无解.

所以这户居民3、4月份的用水量分别为4m3和11m3

阅读理解

A few days ago my wife sent me out to buy something. When I came home, I handed(交给) her a paper bag and said, “Here are the apples you wanted.” She looked in the bag, and then she looked at me. “I told you,” she said slowly, “to buy some eggs.”

I felt worried about my absent-mindedness, so I went to see a doctor. He was a very kind man. “I have seen many people like you. It’s nothing to worry about,” he said. “If you know you are absent-minded, you are all right. But if you do not know you’re absent-minded, you may be really in trouble.”

“Many famous people were absent-minded,” the doctor told me. “Thomas Edison(爱迪生)was standing in line(排队) one day to pay his taxes(税). When he arrived at the window, he found that he had forgotten his own name. He had to ask the man who was behind him to tell him who he was.”

I felt much better and got up to leave. “Thank you, doctor,” I said. “How much do I have to pay you?”

“Ten dollars for the check-up(检查),” the doctor said.

“But doctor, I did not have a check-up!”

For a moment the doctor looked puzzled. Then he said, “Oh, yes, it was the patient before you who had a check-up. How absent-minded I am!”

小题1:It can be inferred from Paragraph 1 that when the author’s wife heard what her husband told her, she was ______.

A.excited

B.surprised

C.sad

D.proud小题2:The doctor took Edison’s story for example ______.

A.to show absent-mindedness is common among people

B.because he liked telling stories

C.to make the author laugh

D.to make fun of Edison小题3:The underlined word “absent-mindedness” in the second paragraph probably means ______.

A.a feeling of anger

B.a feeling of sadness

C.an emotion (情绪) of excitement

D.a trouble in which people often forget this or that小题4:According to the passage, who was (were) absent-minded?

A.Only the author.

B.The author’s wife.

C.The author and the doctor.

D.The doctor alone.

单项选择题