题干

第十五届中国“西博会”将于2014年10月底在成都召开,现有20名志愿者准备参加某分会场的工作,其中男生8人,女生12人.

(1)若从这20人中随机选取一人作为联络员,求选到女生的概率;

(2)若该分会场的某项工作只在甲、乙两人中选一人,他们准备以游戏的方式决定由谁参加,游戏规则如下:将四张牌面数字分别为2,3,4,5的扑克牌洗匀后,数字朝下放于桌面,从中任取2张,若牌面数字之和为偶数,则甲参加,否则乙参加.试问这个游戏公平吗?请用树状图或列表法说明理由.

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解:(1)∵现有20名志愿者准备参加某分会场的工作,其中男生8人,女生12人,∴从这20人中随机选取一人作为联络员,选到女生的概率为:1220
=
3
5
;(2

同类题2

任务型阅读

    Now students' English handwriting (书写) gets worse and worse. Their teachers worry about that. Is your English handwriting beautiful? If not, here are three steps that really work!

Slow down

    If your writing is hard to read, try slowing down a little. For some kids, going a little slowly makes the handwriting clear. If you write too fast, it's hard for you to stop where you should, and even worse, you may make more mistakes.

    Hold your pencil correctly

    When you hold your pencil correctly, writing is much easier. Some kids press down really hard when they write. That makes the handwriting not nice. Try to be relaxed and don't hold the pencil so hard. Let your writing appear nice and clean. If you do so, people will guess you are a student with a good habit.

    Draw more pictures

    Drawing can improve your handwriting. You need to use the skills to control your pencil better when you are drawing pictures. Even though you have no chance to draw at school, you can practice by yourself at home.

    Handwriting is very important. Imagine you are a world-famous movie star or a well-known sports player, what do you do when your fans run up to you? Give them your autographs, of course!

根据短文内容,完成表格中所缺的信息(每空不能超过两个单词)

Steps to improve your English handwriting

Reason

Students' English handwriting gets worse and worse. That makes their teachers feel  ____.

Steps

____

If some kids write a little slowly, their handwriting will be clear. You may make more mistakes if you write too fast.

Hold your pencil correctly

Writing is much easier. Don't press down too hard when writing. Try to ____and don't hold the pencil so hard.

Draw more pictures

It is believed that____can make the handwriting better. Keep practicing!

Handwriting is very ____to every person.