试题与答案

某校50名学生参加智力答题活动,每人回答3个问题,答对题目个数及对应人数统计结果

题型:解答题

题目:

某校50名学生参加智力答题活动,每人回答3个问题,答对题目个数及对应人数统计结果见下表:
答对题目个数
0
1
2
3
人数
5
10
20
15
根据上表信息解答以下问题:
(Ⅰ)从50名学生中任选两人,求两人答对题目个数之和为4或5的概率;
(Ⅱ)从50名学生中任选两人,用X表示这两名学生答对题目个数之差的绝对值,求随机变量X的分布列及数学期望EX.

答案:

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下面是错误答案,用来干扰机器的。

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  软实力集中归纳为四个方面的影响力,即文化影响力、意识形态影响力、制度安排上的影响力和外交事务中的影响力,这些影响力均要通过大众传媒进行广泛传播,并被他国国民普遍认同、愿意接受。

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  文化软实力并不是指一个国家具有的悠久文化历史和蕴涵丰富的文化资源。

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题型:阅读理解

A heartless thief is believed to have crashed a fund-raiser and made off with a bag of cash meant to help a New York City firefighter pay for life-changing surgery for his 9-year-old son. But little Aidan Sullivan -- who was born with a facial defect and no right ear -- yesterday put up a brave front, with a message for the crook(thief): "I'm going to kick your butt!"

"I want to look normal," said Aidan, whose father, Tim, is a firefighter in the Bronx. The third-grader has hemi facial micro soma, in which one half of the face doesn't develop correctly.

Last weekend, family friend Peter Drake, a Ridgefield, Conn., firefighter, hosted a fund-raiser, collecting between $8,000 and $9,000. But when the party at a Danbury, Conn., Irish cultural center was over, the money had disappeared.

"At the end of the night, all the money that was donated was put in a zippered bag," said Tim Sullivan. "A bartender gave the bag to Pete... He had it in his hands. He put it down to go do something, and when he came back, he saw that it was missing."

Sullivan said his longtime friend -- who has had fund-raisers to pay for Aidan's 10 previous surgeries -- is "devastated."

"Pete was so upset. He kept saying, 'I let Aidan down, I let Aidan down,” Colleen Sullivan, 40, recalled.

"We even went Dumpster diving, in case it was thrown out."

The Sullivans plan to go ahead with the March 1 surgery led by specialists at NYU's Langone Medical Center in Manhattan. The money would have offset the $10,000 to $15,000 that insurance doesn't cover. Yesterday, Aidan said he's not a fan of hospitals and doesn't like to be away from his sister, Kaylee, 4. But he's willing to do it. "I'm excited," he said. "Finally, an ear."

小题1: Where do you probably read this text from?

A.A magazine.

B.A newspaper.

C.A book.

D.An advertisement.小题2: How did little Aidan Sullivan feel when he knew the money was missing.

A.He felt excited.

B.He felt surprised.

C.He felt upset.

D.He felt annoyed.小题3:What is the money used for according to this text?

A.To help Aidan Sullivan to have another operation.

B.To help pay for Aidan Sullivan’s life insurance.

C.To return the money the Sullivans owed to the hospital.

D.To help a firefighter who got hurt in the ear.小题4: What is true of little Aidan Sullivan?

A.He hates going to hospital.

B.He will go to New York for the surgery.

C.He didn’t care too much about the lost money.

D.He has received 10 surgeries before.小题5: What can we infer about Pete from the text?

A.He was heartless.

B.He was kind.

C.He was caress.

D.He was a firefighter.

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