题干

在400米的环形道路上,A、B两点相距100米.甲、乙两人分别从A、B两点同时出发,按逆时针方向跑步,甲每秒跑10米,乙每秒跑9米,每人每跑100米都要停10秒.那么甲追上乙需要多少秒?

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答案(点此获取答案解析)

解:如果如果乙在甲的前边,则两人相距100米:

假设甲乙都不停地跑,那么甲追上乙的时间是100÷(10﹣9)=100(秒),

(100÷10﹣1)×10+100

=9×10+100,

=190(秒).

答:如果乙在甲的前边,则两人相距100米,甲追上乙需要190秒.

如果如果乙在甲的后边,则两人相距400﹣100=300米.

190×3=570(秒).

答:如果乙在甲的后边,则两人相300米,则甲追上乙要

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How to become a better runner

  This is meant for runners in high school .If you want to become a better runner, then here are several things you can do.

  Connect with your team if you are new. ____ .You can ask them for advice and hang out with them outside of practice!

  If you have a workout,don’t slack off(松懈) ever.This will never improve your performance .

____ .I know some people say they do it just to stay in shape,but if you want to stay in shape you have to work for it!

  Run 6 out of  the 7 days in a week, but don’t work out on your days off. You need to relax.

____ .It dosn’t have to be as much as you would run during practice, but you should still exercise so that you don’t get out of shape.

  If you are injured, do not run. ____ . It’s common to get shin splints(小腿酸痛), so if this happens to you ,just take a break from running. It will actually make you better once you start running.

    ____ .It allow you to form a relationship with other people like a family. If you take time to become a better runner, you will be physicaaly and mentally(精神上地) stronger.


A, It takes much of your time.

B,Running is more than a sport.

C,Running can make problems worse.

D,It is an experience that you will never forget.

E,But if you are having a long break , you should still run.

F,Remember that you are supposed to run in a running sport.

G,It helps you realize that there is more to just the sport to look forward to.