问题 单项选择题

从1、2、3、4、…、12这12个自然数中,至少任选几个,就可以保证其中一定包括两个数,它们的差是7( )

A.10
B.9
C.8
D.7

答案

参考答案:C

解析: 这12个自然数中,差是7的自然数有以下5对:{12,5){11,4){10,3){9,2){8,1)。另外还有2个不能配对的数{6){7)。可构造抽屉原理,共构造7个抽屉。只要有两个数取自同一个抽屉,那么它们的差就等于7。这7个抽屉可以表示为:{12,5){11,4){10,3){9,2){8,1){6){7},显然从7个抽屉中取8个数,则一定可以使有两个数字来源于同一个抽屉,也即满足差为7。

单项选择题 A1型题
完形填空
My name is Nick Vujicic, an Australian who was born without any limbs(四肢). In recent years one of my most 36 videos on YouTube shows my skateboarding, surfing, playing music, and best of all, 37 hugs from all fields of great people.
All in all, those are pretty ordinary 38 that just about anyone can do, right? So 39 do you think that video has been viewed millions of times? My theory is that people are 40 to watch it because in spite of my physical limitations, I’m living 41 I had no limits.
People often think someone 42 a severe disability to be inactive, upset, maybe even crazy. But I’d like to 43 them by showing that I lead a very adventurous and fruitful life
Among the hundreds of 44 on that video, here’s one typical remark:” seeing a guy like this being happy makes me wonder why I feel 45 for myself sometimes -or feel not funny enough, or whatever. How can I 46 think thoughts like that when this guy is living without limbs and still being happy!?”
I found happiness when I realized that imperfect 47 I may be, I am the perfect Nick Vujicic. I’m designed 48 God’s plan. That’s not to say that there isn’t 49 for improvement. I’m always trying to be better so I can better 50 the world!
I do believe my life has no 51 . I want you all to feel the same way about your life, no matter what your challenges may be. As we 52 our journey together, please take a moment to 53 about any limitations you’ve placed on your life. Now think about what 54 would be like to be 55 of those limitations. What would your life be if anything were possible?
小题1:
A.disappointingB.unforgettableC.popularD.useful
小题2:
A.receivingB.collectingC.returningD.gathering
小题3:
A.sportsB.activitiesC.affairsD.wonders
小题4:
A.howB.whatC.whenD.why
小题5:
A.drawnB.expectedC.requiredD.ordered
小题6:
A.even thoughB.in case C.as thoughD.if only
小题7:
A.ofB.fromC.inD.with
小题8:
A.adviseB.greetC.surpriseD.please
小题9:
A.commentsB.picturesC.repliesD.statements
小题10:
A.nervousB.sorryC.eagerD.desperate
小题11:
A.stillB.everC.alsoD.even
小题12:
A.ifB.as C.whileD.although
小题13:
A.according toB.thanks toC.owing toD.up to
小题14:
A.stageB.areaC.placeD.room
小题15:
A.protectB.rescueC.serveD.reserve
小题16:
A.challengesB.limitsC.doubtsD.endings
小题17:
A.finishB.continueC.startD.stop
小题18:
A.worryB.thinkC.careD.talk
小题19:
A.weB.oneC.itD.you
小题20:
A.freeB.shortC.awareD.fond