问题 填空题

利用计算机产生0~1之间的均匀随机数a,则事件“3a-1>0”发生的概率为______.

答案

由3a-1>0结合1>a>0,可得a>

1
3

则事件“3a-1>0”的概率为P=1-

1
3
=
2
3

故答案为:

2
3

阅读理解

Come and see the Indian elephants and the new tigers from Northeast of China. The beautiful birds from England are ready to sing songs for you, and the monkeys from Mount Emei will be happy to talk to you. The lovely dogs from Australia want to laugh at you. Sichuan pandas will play balls for you. The giraffes from Africa are waiting to look down on you.

Tickets                                                     Opening time

Grown-ups (成人):       ¥3                              9:00 a.m. ~ 4:00 p.m.

Children: Over 1.4m     ¥2                              except Friday

Under 1.4m    Free                           10:00 a.m. ~ 3:00 a.m.

Keep the zoo clean!

Do not touch, give food or go near to the animals.

60.   Why does the writer introduce so many animals from different places to us?

A. To frighten us in the zoo.                B. To make us lovely in the zoo.

C. To attract us to the zoo.                   D. To show that animals can do everything.

61.   How much does Mr. Smith have to pay if he visits the zoo with his son of three?

A. ¥3.                 B. ¥4.                 C. ¥5.                 D. ¥6.

62.   At which of the following time can we visit the zoo?

A. 8:30 a.m. Wednesday.                            B. 9:30 a.m. Friday.

C. 3:00 p.m. Sunday.                          D. 5:00 p.m. Tuesday.

63.   From the passage we can infer (推断) that a giraffe must be a very ______ animal.

A. fat                    B. short                 C. strong               D. tall

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