问题 解答题

在某文具商场中,每个画夹定价为20元,每盒水彩定价为5元。为促进销售,商场制定两种优惠方案:一种是买一个画夹赠送一盒水彩;另一种是按总价92%付款。一个美术教师欲购买画夹4个,水彩若干盒(不少于4盒)。

(1)设购买水彩数量为x(盒),付款总金额为y(元),分别建立两种优惠方案中的y与x的函数关系式;

(2)如果购买同样多的水彩,哪种方案更省钱?

答案

解:(1)按优惠方案①可得

y1=20×4+(x-4)×5=5x+60(x≥4),

按优惠方案②可得

y2=(5x+20×4)×92%=4.6x+73.6(x≥4);

(2)比较

y1-y2=0.4x-13.6(x≥4),

令y1-y2=0,得x=34

∴当购买34盒水彩时,两种优惠方案付款一样多,

当4≤x<34时,y1<y2,优惠方案①付款较少;

当x>34时,y1>y2,优惠方案②付款较少。

完形填空
Thanksgiving Day was near. The Grade 7 teacher asked her students to   16 a picture of something for which they were thankful.
People celebrated the   17  with turkey and other traditional goods of the season. So,   18  of her students’ pictures were about them.
However, Jack made a ___19____ kind of picture. Jack was not the same as other boys. He always looked sad. When asked to draw a picture of something for which he was   20  , he drew a hand. Other students were all very    21  in the picture. Whose hand could it be? One child guessed it was the hand of a farmer, because farmers feed    22  . Another suggested a police officer, because the police   23  and care for people. Still    24  guessed it was the hand of God, for God feeds us. And so the    25  went on until the teacher almost forgot the young artist himself.
When the children had gone on to other subjects, she stopped at Jack’s desk and asked him   26    it was. The little boy looked up and said in a   27  voice, “It’s yours, teacher.”
She remembered the times she had taken his hand and   28    with him here or there, as she had with the other students. She often said, “   29  my hand, Jack. We’ll go outside.” Or, “Let me show you how to use your pencil.” Jack was most thankful for his  ___30____ hand.
小题1:
A.printB.findC.drawD.take
小题2:
A.festivalB.weekC.nightD.Sunday
小题3:
A.littleB.noneC.fewD.most
小题4:
A.niceB.differentC.sameD.best
小题5:
A.thankfulB.pleasedC.sorryD.afraid
小题6:
A.sadB.interestedC.carefulD.angry
小题7:
A.chickens B.dogsC.cats D.turkeys
小题8:
A.hurtB.protectC.harmD.smile
小题9:
A.anotherB.otherC.othersD.the other
小题10:
A.tileB.speechC.discussionD.talk
小题11:
A.whatB.whereC.whichD.whose
小题12:
A.high B.lowC.hardD.beautiful
小题13:
A.walkedB.saidC.sangD.taught
小题14:
A.Touch B.LookC.TakeD.Push
小题15:
A.mother’sB.classmate’sC.teacher’sD.friend’s
单项选择题