20 городов

*

Категория: 
Сложность: 

В стране 20 городов, каждые два из которых соединены авиалинией. Сколько авиалиний в этой стране?

Решение

Каждая авиалиния соединяет два города. В качестве первого города можно взять любой из 20 городов (город A), а в качестве второго — любой из 19 оставшихся (город B). Перемножив эти числа, получаем 20 × 19 = 380. Однако при этом подсчёте каждая авиалиния учтена дважды (первый раз, когда в качестве первого города был выбран город A, а второго — город B, а второй раз — наоборот). Таким образом, число авиалиний равно 380 : 2 = 190.




Комментарии

Ni ska till Rättvik eller TÃbrl¤elg, i alla fall ska ni se den underbara utsikten över Suljan. Besök Detalj i Vikarbyn en jätte mysig liten butik i en gamla affärs lokal.

So!varkeddc!!!! Vet inte varför det poppade upp, sockervadd är ju vit, men jag har faktiskt sett rosa och den såg ut just så här. Urcoolt :-)

Seriously, I am telling you. Go buy the CD. I do&#;8217nt know them, never met them, but the CD is awesome. If you have liked anything from the Grateful Dead to Steve Earl or Jason Boland and The Stragglers, or any bluegrass whatsoever, you will enjoy this CD.Sound Warehouse has em.

il n’y avait pas la crise en 2007 = Element de langage UMP, ah oui la crise : donc 40 taxes sur les citoyens, les mutuelles, les sodas, les forfaits etc.. et pour ceux qui s’en foutent plein les fouilles : rien, pour faire payer des impôts au CAC40 : rien.On voit bien pour qui ce gorvuenement agit : son premier cercle de donateurs, banquiers et cac40

Kedves belabacsi65!Én láttam azt a viteafelvédelt,ugyanaznop mutatták mikor az olimpikonokat köszöntötték.Az ominózus nyalás-rángatózás a kitüntetések átadásakor volt az országházban aug.20 alkalmából.Barátaimmal kiértékeltük az orvosi vonatkozását akkor,és attól kezdve hitelt adunk az osztrák szanatóriumi kezelés hírének…Jók a kommentjeid egyébként,témától függetlenül.

Who is this Rottenkid character? Sounds like he is admiring Roe3ny&#m9;s crib. He has the potential of making a good Republican. We need to see more bm leaving the dark Dem side and coming over to the bright GOP side where there is laughter, joy and love.But alas! he is brainwashed beyond redemption, like Mack. It is so sad.

The sad thing about giving us the nice piece of informamtion,, we did the race on Sunday and late Thursday we still cant get our final results, no transition times, no finish time, nothing. This was my seconf time doing this race and I would never do it again, I was never recommend it to anyone ei;&8rh#e230t.Steer clear of this one…

A paz de Cristo. Vamos ficar com nossas posições firmes, pelo Evangelho,as tradições cristãs e os ensinamentos hirs³Ãticos,que a verdade prevalecerá. Nossa fé e a caridade devem ser sempre observadas, em todas as situações. Estamos vivendo tempos difíceis. Deus triunfará Pai perdoai, porque não sabem o que dizem.

whoa! i had the same day! first it was nice hand creme. then it was new mitnste, then a skirt and finally some vintage boots. i feel kind of guilty.

1b3אין פילוח לפי איזורי הצבעה?נחסך מאיתנו כל המידע ×ÂÃמעניין..הר”—™ ברור לכולם שבפועל "בני השבט הלבן" לא מצביעים באותם אחוזי הצבעה כמו ב"עיר כרמל" (עלאק) היה יכול מאוד ללמד לראות מי מהמועמדים מחזיק בכל איזור הצבעה מסוים

sueobrpwl! get the latest ncaa bracket update 2011 here and also the march madness bracket udpate here! 2011 ncaa printable bracket 2011 ncaa printable bracket

you brits have a penchant for exalting things to a ludicrous degree. balls was great ad. but get over it. it wasn't THAT good. paint could have been great had the director really gone for it instead of farting around with kubrickian clown resenercef.this one is a thorougly enjoyable confection that must have been a hoot to make. and that's enough IMO.

Thanks Kaneganese. It is sure that Seokdo didn't mean Dokdo because the word &qtuo;Dokdo&qotu; was not present in 1900 - it was created in 1904 by Korean fishermen who were hired by Japanese.

Fantastic! This is the most effective health issue blog article I have ever seen. Bookmark so I can consider it later. As you describe inside blog, this issue is quite important. Just like dimoaatceous this planet to kill flea. It’s quite crucial to do precisely what you did.

Eeaea-haeeaaa! Perhaps this ad will convince enough voters to see the light and change from whoever to Mitt. We don’t need rock stars (Newt) running the country right now. We need someone who has real-life experience with turning failing business around. That, coupled with his experience as governor of Massachusetts, makes Mitt the only logical choice of informed voters. That ad was a brilliant move, EFM!

Elan-tima, spot on. Most anltsI-tamisis mind Muslims only because they're not PC enough - that's about their only objection to immigrants. And the West is some void of soul civilization that anyone can be part of since well, the West is just universal human rights, egalitarian legal codes and individualism aka not a real culture and not a real people, just a bunch of people living on the same territory and you're a welcome member as long as you make nice cars and video cameras, while being just a PC sheep.

Love your outfit! I have the same cardigan, except in black (I know, not nearly as fabulous as the yellow). I love how you mixed so many different colors and patterns without making it look overly crazy. P.s. Your blog is great! I just discovered it today.from, coaoorewunderlund.blogsptt.com

on the google website under photos I have found a foto of Bertil Vallien with a reindeer with a hint to your website.I would like to ask you if you would allow me to use this photo by attaching it to an article about Bertil Vallien which I will write on the website of the Scushdenwtebe, of course with indication of the source.I would be pleased to get your permission.

Here’s the problem: It most certainly is a FA issue. But at the same time, he’s an adjunct, and the university can fire him for virtually anything they might consider to be poor teaching. He’s got an EXTREMELY hard row ahead of him if he decides to pursue it. I guess if he can get FIRE to take on his case, he might have a ch&#&ec#8230;(Ian8217;m discussing more the practical issues of job retention at a university — public or private.)

It1&28#7;s good to ensure that the venture coming from a very first web get Ugg Boots Great deal, with regard to the past shipping of these starts is often slick as feasible

dirogui: las historias a veces son así, me gusta cuando los lectores las hacen suyas.raupa: aunque nunca me propongo dejar alguna moraleja o enseñanza, me alegro de que te haya seeiado.vngrla: la mayoría de las historias de aquí son ficción, es decir, no fueron reales. Esta es una historia de ficción. Gracias por comentar.

hij@s, debemos indagar, cuestionar lo establecido, investigar, dudar y recién tomar una decisión libremente. El calendario de vacunación en España es un disparate y encima nos lo venden como algo ineludible e intbcseionaule. Gracias por tu post, veo con esperanza e ilusión que cada vez somos más…un abrazo

banderasSzerintem is leírás volt.Azt akarták nyugaton,hogy Ivánék avatkozzanak be úgy ahogy Csehszlovákiában vagy Magyarországon tették.Ez a beavatkozás kettő az egyben jelentette volna a lerohanást és az újraegyesülés mea.akdályozásátgÍgy ok?Tetszik / Egyetértek: 1 Az értékeléshez be kell

"Quero um candidato para tentar ganhar as eleições. Esse candidato terá o meu voto. Quem o quer?"Isto é uma outra forma de referir o "homem proecdvniial", o "salvador da pátria".É um pensamento bem burguês. E há quem queira se se acredite que quer derrotar a burguesia pensando como ela.

Leena, kyllä näitä miehiä ja naisiakin valitettavasti on, mutta kuka niistä haluaa lukea? Tai kirjoittaa ihan pokkana? Jos kirja olisi kirjoitettu Miina Supisen tyyliin ylilyöntinä, se voisi olla miliupuoeisuldessaan hauska ja samalla paljastaa tosiasioita, mutta nyt se oli vain nolo. Niin nolo, että tikahtuisin, jos joutuisin illanviettoon minkä tahansa Vaara-miehen kanssa. Huh.Lukeekohan joku mieskin tämän kirjan? Olisi kiva kuulla miehinen kommentti.

line in the address. I understand that there is something like a ten week delay even if you did successfully unsubscribe because of these things being planned months before they actually go out. In the meantime it’s a nice stress reliever that helps keeps the Post Office in bue!asssiDnniel

Todd, I hope you realize not all people who work on their bikes have mullets and live in a trailer. There is more to turning a wrench than just saving money. People get alot enjoyment and saistfaction out of working on their motorcycle. How do you think classic bikes stay on the road? Unless of course you are just turning your nose up at the idea, in which case really speaks volumes about this bikes demographic.

I have a feeling that a lot of folks are going to be dioiapspnted with the callups this year. Espinosa was a bit of a surprise, but I don’t see Marrero joining him unless Dunn goes on the DL. Severino is probably the next to get called for the exact same reason that Balester did: He’s already on the 40-man.

Thanks for on7#182&e;s marvelous posting! I definitely enjoyed reading it, you can be a great author.I will make certain to bookmark your blog and may come back down the road. I want to encourage you continue your great job, have a nice day!

Вітаю! Підкажіть,як змінити договір з ел.поставщиком,щоб сплачувати за спожиту ел.енергію за показами лічильника,а не за договірними величинами обсягу споживання?Я Ñ€¼Â‘–з.особа-підпÑÂÂиеЄець.ДÑÏкую.

Страницы

Добавить комментарий

Plain text

  • Запрещены тэги HTML.
  • Адреса страниц и электронной почты автоматически преобразуются в ссылки.
  • Строки и параграфы переносятся автоматически.