Combinations and permutation

[specter290]

rofl this video was uploaded 4 years ago, but it works wonders, Youtube is the future of school!!

[bionicturtledotcom]

@specter290 thank you! Yikes, this was one of the first videos I recorded, Geez, I can't believe i took 10 seconds to introduce (and i don't do music intro anymore; I've learned you need to cut to the chase), But I'm so glad it's still useful ... i do totally agree that youtube is the future of school (our channel is in the new YouTube for Schools).

[akshy1996]

Thankyou for uploading this. Really helped me. (:

[YGMH1107]

If they're sitting around a round table as it sounds from your example, then you're answer is wrong It will not be 5P3 since some of the orders will be repeated as there are three ways for Superman to be to the left of the magician for example

[bionicturtledotcom]

@YGMH1107 the table isn't round, you can just look, I don't see how it "sounds" like a round table. But actually, a round table doesn't change the answer: those "shifted" arrangements are simply permutations. So, I disagree with your correction. But feel free to show me what you think the number should be

[YGMH1107]

@bionicturtledotcom My point wasn't that the table is actually a circle! Whatever the shape of the table, there will be people sitting around it and thus ABC can be equal to BCA in terms of position - for example ABC is the same as BCA because B is sitting to the left of A and C is to the right of A in both situations.

The correct answer should have been TWO, there are only two different ways to seat 3 people around a table - ABC and BAC (ACB would be a repeat of the second option

[bionicturtledotcom]

@YGMH1107 your def requires a circular table & ignoring the def of permutation, yes? you need a circular table so BAC equals ACB only bc "B is to the left of C." This in not true for the rectangle. Further, yours needs indifference to the seating position. If 'A' in ABC is next to the heater, then "B" is next to the heater in BAC ... IMO, "permutation" implies seating position matters! So ... i still don't buy your correction but thank you for clarifying why you say so

[bionicturtledotcom]

@YGMH1107 more succinctly, your assertion that "there are only two different ways to seat 3 people around a table" requires assumption(s) that negate the definition of permutation. I would say there are 6 ways to seat 3 people: 3 * 2 * 1, because position matters in a permutation, by definition, as sequence matters. In fact, you do require a circle to nullify this assumption (IMO)!

[danielle82818]

nosebleed! ouch

[Tribal1693]

fuck statistics

[opaaul]

thankyou verymuch. this helps me a lot :)

[joepinkful]

youtube is the future of school.

[specter290]

@joepinkful totally agreed, my statistics textbook doesnt give me the attention and care that boinicturtledotcom does.i finanly understand permutations and combinations and will be fully equipped for the upcoming test, thank you

[beinthesummer11]

Somehow relearning this in university was 10 times harder than initially learning it in early highschool. Thanks for the refresher, extremely clarifying!

[bob123rulz]

In my opinion, you are an explaining boss.

[ikmal017]

Thank you!! my additional mathematics teacher made it a lot confusing. Thanks to this video I finally understand the concept of using n & r

[khomphuong]

thanks



[MrJamesjamespark]

after graduating from my high school 30 years ago, today I finally understood the difference between c and p. thank you so much!!!

[31temper]

you save us from a world of horrible high school teachers.

[specter290]

@31temper and the dry textbooks... 

[awesomejoe12]

Excellent video to watch right before my test. Very informative and to the point. Thank you!!!

[CFAStudent]

excellent video, ive had problems understanding this for ages until now. thank you!!

[judynic1992]

kool

[kirpaangad]

Thank you so muchhhhh!!!!

[superjtrdr]

I was having trouble with order matters vs doesn't matter. I went through a week of confusion for nothing. You clarified the difference in a way that made sense

thanks

[SkyPilotage]

Isnt nPr= n(n-1)(n-2)...(n-r+1)??

Anyways, keep up the good work helping us :)

[downshifttt]

thank you

[asda110knm]

thanks! good explanation :)

[xXiTzLeGiTXx]

So basically a combination is the permuatation divided by r!

[Genesis5964]

Hi thanks to your clear tutorial. Is there a formula in getting all the specific possible combinations.

[mrmichael20]

Thank you for your time :) don't thank us, we should thank you for you time. This is one of the best lessons I ever watched.

[brianappa]

Thank you so much! :)

[usachanrocks]

love the the superman guest! lol

very well explained.

[alfatourist]

I found you to be the best in explaining permutation & combination because you compared them & made it easy to understand, and also made the point when you said there are fewer combinations than permutations. I think you are a great teacher.

[sherifnosseir]

thanks a lot man... appreciated...

very well explaination... unlike my teacher... IF AND ONLY IF order matters... do this...

[DEEPTI988]

good i

 like the idea of animation

[elrynx2]

THANK YOU SOOOOOOO MUCH!

 I have school in 4 hours and I haven't yet gone to bed.... math tests suck!

[PhilESkyline215]

I'm confused on the last one with the poker hand.

I thought it was 52!/47! 5! which comes out to be 52*51*50*49*48/5*4*3*2 which gives you 311,875,200/1800 for 173,264.

Where did I go wrong?

[henriser123]

@PhilESkyline215 I lost a friend

[Advaidhcowsella]

@henriser123 somewhere along

[dayunyor19]

thanks....that was clear....

[PrincessAlmika]

thankyou

thankyou

thankyou!!!!

(:

[gabrielacarchi]

Thank you so much!! :o)

[2eadhla9]

Thank youuu! .

[2fast2furiousDevil]

you just saved my math grade thank you very much

[BoboLover95]

thanks , i really get how to do it.

[canticle80]

What does the exclamation point mean?

[KodeLiMe]

The exclamation point in math means "factorial." This means that you multiply 5x4x3x2x1, where you take take 5 and multiply all the way down to one. If it were 9!, you would just follow the same pattern: 9x8x7x6x5x4x3x2x1 and 300! would be 300 all the way down to 1...which would be an enormous number that pretty much no TI calculator could display :)

[chubble101]

FACTORIAL!!!!

[Swiftman13]

factorial

[BOGZASV8MA]

excellent - you save people alot of money in tuition.

[assyrian]

I watched this and I got it right away. THX!!

[SeFu2006]

my math teacher didn't explain this as good as you

[CabcK]

Fantastic simplification. The efforts that went inside are indeed commendable. Perhaps you could try to remove the proprietary software out of these learning exercises, and try to explain using Free Software - for the larger benefit of the world's people.

[lingyif]

oh wow!!! im outa words to say....

this is AMAZING!

i had sooo much problems with the "order does not matter/does matter" thing!

u just totally explained them in a perfect away!

[gaidee]

amazing! I can just agree with phatcat012 ! Thx a lot for that top video!!! Hope there are more videos from you on here....))))

--->5 stars by the way

[phatcat012]

you are officially my hero of the day... I was having so much difficulty with this and in seven minutes you explained it all! Thank you!

[tihutan]

thank you, very usefull!!!!

[brettrobbie]

hi can you tell me where to see ymore videos like this

you did a great job

thank u

[lkpeay]

i do not have a quiz (today) but i needed to find out how to do nPr and nCr on both the ti-83 calculator and in excell...

i am 37 years old...

what the hell did we do B4 the internet?

[charlesandhisworld]

Just plug the numbers into the calculator man, find the nPr and nCr buttons!

Easy

[chipyto]

45 minutes before test thank you in less than ten minutes i understud what my teacher could not explain to me in two whole clases

[12oink12]

wow thanks.. with 6 hours to go till my exam, you might have saved me.

[jasonmason29]

Very well explained i ve been trying to find a simpel example and you did it!

[TrueCourse]

Ditto! Most other tutorials somehow don't explain the concept as simply as this. Something that I could keep in my li'l mental pocket. Thanks loads!

[peopleboss]

this is great! tx for the help!

[jesusrulesflight]

thanks

my teacher didn't explain why what happens

[Rianto22]

Thanks!

[beztia88]

this is relly helpfull tnks a lot

[tvij21]

all your tutorials are awesome! do u have more on advance stats or probability & also for standardize tests like GMAT

[unixxed]

Good tutorial, thank you. I'm going to check out your other videso see if you have any more detailed videos on the same topic. Appreciate your help.

[QuadraticNerd]

it's about time somebody explains this correctly. I FINALLY get it!