题干

某车站在检票前若干分钟就开始排队,设每分钟来的旅客人数一样多,开始检票到等候的队伍消失,若同时开4个检票口需30分钟;同时开5个检票口需20分钟,为了使15分钟内检票队伍消失,需至少开多少检票口?

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答案(点此获取答案解析)

解:设1个检票口1分钟检票的人数为1份.因为4个检票口30分钟通过(4×30)份,5个检票口20分钟通过(5×20)份,说明在(30﹣20)分钟内新来旅客(4×30﹣5×20)份,所以每分钟新来旅客:

(4×30﹣5×20)÷(30﹣20)=3(份)

假设让3个检票口专门通过新来的旅客,两相抵消,其余的检票口通过原来的旅客,可以求出原有旅客为:

(4﹣3)×30=30(份)或(5﹣3)×20=40(份)

让3个检票口专门通过新来的旅客,其余的检票口通过

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AfterSteve Jobs died, his friend Larry Ellison said something like this, “There willnever be another Steve Jobs.”____ Larry wrote this list of Steve's life lessonsto remind us all.

Love what you do.

SurelySteve became a billionaire when he brought Apple back. Apple was hiscalling—even after he got fired from the company. We all have bad jobs at onepoint in our lives. But the question is:amI in the right job? Have I found the right company? Life doesn't go on forever.____

Don't do it all by yourself.

Stevelearned a great leader can't do it all by himself. He needs people. They mustbe talented.____ They must be given the opportunity to succeedand fail. In short,youhave to learn to be a great leader if you want to see your great ideas and hardwork truly have an influence on the world.

____Appleis always the best at creating a new product that meets the exact needs ofusers. It's empathy (同情心)that helps Apple achieve this. Whenever the user has the first touch with a newApple product, he says“Wow, it's just what I need.” Remember: you're King inthe business world if you know exactly what consumers desire.

Don't mess around with your health.

____ That's the most important lesson from Steve'slife. It's great to learn from him now, but the fact is that he should still behere if he had treated his cancer properly. Instead, Steve chose a naturopathic(自然疗法的)solutionthat wasn't effective. When he finally decided to take his doctor's originaladvice ,itwas too late.

A.They must be inspired.

B.Be the best in your field.

C.Take your health seriously.

D.Get on your right path now.

E.Will this lead to a successful career?

F.Put yourself in the other person'sshoes.

G.What are the key things that we canlearn from him?