问题 解答题
为加强对学生的社会责任感和爱国主义的教育,某学校团组织在清明节节到来之际计划租用6辆客车送一批团员师生去烈士陵园扫墓.现有甲、乙两种客车,它们的载客量和租金如下表.设租用甲种客车x辆,租车总费用为y元.
甲种客车乙种客车
载客量(人/辆)4530
租金(元/辆)280200
(1)求出y(元)与x(辆)之间的函数关系式,指出自变量的取值范围;
(2)若该校共有240名师生前往参加,领队老师从学校预支租车费用1650元,试问预支的租车费用是否可以结余?若有结余,最多可结余多少元?
答案

(1)租用甲种客车x辆,则乙种客车为6-x,根据题意得:

y=280x+(6-x)×200=80x+1200(0≤x≤6);

(2)由“该校共有240名师生前往参加,领队老师从学校预支租车费用1650元”得:

80x+1200≤1650
45x+30(6-x)≥240

解不等式组得:4≤x≤5

5
8

∴预支的租车费用可以有结余.

∵x取整数,

∴x取4或5.

∵k=80>0,

∴y随x的增大而增大.

∴当x=4时,y的值最小.

其最小值y=4×80+1200=1520元,

∴最多可结余1650-1520=130元.

阅读理解

You can buy chewing gum in nearly every country of the world. ① But it wasn’t always like that.[

The American Indians were the first people to chew gum. This gum came from a special tree that grew on their land. In 1848, a sailor called John Curtis began selling it. He was the first person to sell chewing gum. The gum he sold cost just a few cents for two pieces. It became popular very quickly even though it was very hard to chew. ② Nowadays, other things are added to the gum to make it soft and sweet.

By 1890, there were hundreds of different chewing gums. The most famous name in chewing gum, however, is probably William Wrigley. He spent a lot of money in advertising and even sent free pieces of gum to children on their birthdays. ③ He also said that chewing gum helped people work better and that it stopped people from feeling tired.

Although today many millions of people chew gum, not everyone thinks it is a good thing to do. Many people think it is dirty. The Singapore government does not allow people to buy chewing gum. One reason for this is that when some people have chewed all the taste out of their piece of gum, they take it out of their mouths and put it on to the backs of seats or other places. 

小题1:请将①处翻译成汉语。________________________

小题2:请根据②处内容完成下面句子。(每空一词)

People make chewing gum soft and sweet _________something to it.

小题3:把③处改为直接引语。(每空一词)

He also said“, Chewing gum______ people work better and it ______people from feeling tired.”

单项选择题