Calculating the Probability of Simple Events

[kurniautami]

thanks :)

[96ruly]

One reward bag contains 10 slips for pandas,6slips for monkeys,6 slips for lions,and 8 slips for kittens.What is the chance of drawing a slip for a panda? please help!!!!

[Multigameguy35]

people say to me "you write like such a lefty" since my handwriting is absolutely terrible but look at the numbers you wrote, they look almost perfect, and you're a lefty, so, take that LILY!

[TheShawntel31]

awwww thx sooooooooooooooooooooooooooooo­oooooooooo much now i get it...i would probably donate to but college is eating my money up!!!!!!!

[konstantinoscharlaft]

Romans wanted to spend less days on february when they made the calendar because it was the month of praying and they got bored and gave the days to july and august who were months named after emperors

[camelsmaycry]

thanks 

[MYLCJAZZELL]

You make it this so much easier to understand than my Professor. Thank you so much.

[prodev05]

Nice and easy to understand. Good work.

[antediluvian99]

The probability of getting head and some tail... by just flipping a coin... on a saturday nite is P(As/Mou) = a lot of beer. [ I know I know, it's sleazy but I hearing 'head' like a thousand times just stir something in me.]

[burkerow]

@MrPacquiaomayweather Why do you use "dickhead"? Was that necessary in this forum? I have a different opinion as to whom deserves the epithet of "dickhead".

[ohare1916]

i should of studied math at university instead of law. i find this strangely interesting

[mzzswankychocolate]

hmmm god does really help yes...thank him for putting up d videos to help us out

[mrkoollll]

what is the differences between the probability that an event will occur and the odds that it will occur

[TheBlueHeroes]

I understand just about everything with these, as you say, "simple" Probability calculations - However, the idea of Jan. having one day and Feb. having. 364 days (and therefore there's a greater chance of "the answer" being Feb.) doesn't quite click.

Surely realistically it would be a 50/50 chance.. Imagining one side of a coin is Jan. and the other side is Feb. - 50/50 right?

OR am I not allowed to think that way with THIS CERTAIN EXAMPLE?

Please enlighten me, haha.. Not sure which way to th

[gamesbok]

In a leap year February has 29 days, and the difference between 28/365 and 29/366 is 0.00025226.

[bonsly21]

5:19 i dont get where you got the 2 from

[xxxjovannyxxx]

@bonsly21 two sides of a coin, bro

[bonsly21]

@xxxjovannyxxx oh ok. thanks



[Zenithlikespie]

Thank you so much, sir. You give me hope to pass my final and my math class itself. Thanks again!

[EMINEM6890]

thnx listening to teachers is boring and slow (does go to my head)

XD but videos helped

[MrAlix777]

thanks for help it helped me pass my test

[FestIf0012]

dude thanks taught me alot 

[0teh0killah2]

What I have a hard time grasping - and would appreciate some clarification - is if, in the second example, the probability would be greater if the three coins were flipped simultaneously? Because then HHT would equal THH, right? It seems odd to me that the act of looking, or delaying a coin toss, would somehow effect its probability. Thanks.

[patrickJMT]

@0teh0killah2 not sure i quite understand. tossing the coins 'one at a time' or simultaneously makes no difference, you are correct. imagine that the coins are different colors so that we can distinguish which coins have heads and which have tails. by flipping one at a time, one would notice this distinction.

so no, HHT is not the same event as THH.

[Supervillain725]

@patrickJMT It's all probability, theory and assumption. If you used real world examples then the formulas won't work.

[kaymakliekmek]

@patrickJMT I am sorry but I am still not understanding how these two are not the same events. Why does the order matter here? They are both "having two Hs and one T to me" :/ Thank you in advance.

[wtfiyn]

@kaymakliekmek (in case nobody has explained it to you yet) Think of THH and HHT as numbers, like 234 and 432. They are not both the same, they look like it but the order matters. Just like with flipping coins; flipping tails first is not the same as flipping tails last.

[kaymakliekmek]

@patrickJMT Accordingly in your example of the "and statements" when you write down all possibilities you write H1,H2,H3 for example but not 1H,2H,3H. What is the difference of that situation with this one?

[Supervillain725]

@0teh0killah2 I have a hard time understanding probability as well. Mostly because when my instructor talks about flipping a coin 3x and it landing heads, I just don't care.

[fahan649]

@0teh0killah2 Coin flipping is a theoretical probability were as the phone number scenario is an experimental probability, just wanted to give a little info.

[sunslap]

Does the order in which the event happens really matter?

[Chyaman09]

Uploaded on my birthday! Go Patrick!

[Citroion68]

Why is it multiplication not addition for finding the total outcomes?

and is the expected average outcome value the mode of the choices?

so say you have 1, 2,1,1,1,1,4 on a spinner is the expected average outcome value 1 because it occurs the most? because they gave me a fourmula and its like 1x p(1)+2xp(2)+3xP(3) and I have no idea what that is

[thecapone45]

ok so can anyone answer me this please? lets say im playing a game. and it is 4 people. three of those people are against me,,, so are my chances of winning 25%? (3 against 1 game)

[3816781799]

OMG!! My AP Statistics teacher is HORRIBLE!! He does not teach us at all so we have to teach ourselves. I do not know how to teach myself so your videos have been a BIG help. You are an EXCELLENT teacher. You made it so simple. I wish that I had a million dollars to pay you. I'm going to tell all of my classmates about you.

[789123Y]

When flipping coin, does this mean that no outcome is more likely to happen than the next? Hitting all the heads is as likely as hitting HTTH for example?

[patrickJMT]

@789123Y yep that is correct. any particular sequence is as likely as any other.

[JLchevz]

@789123Y Yes it is, the thing is, there are so many combinations that it is not very likely that you hit the one you want.

[simply21sicilian]

Thanks so much for this stuff! I would probably donate if i wasnt a broke college student : /

[patrickJMT]

@simply21sicilian spread the word about the videos- that is the best donation

[piushr]

awesome..im studying for my GMAT right now and your videos really help :) thanks

[leppardas]

The reason why February has only 28 days is that the months of July and August were made to have 31 days instead of 30 to honour the Julius Caesar and Augustus by subtracting the days of the last month that time - February. At the time before these emperors, the calendar had only 10 months to indicate the most productive months in the year and two extra winter months which were not included into the social calendar. That is why it was so easy to manipulate the calendar in the way it was needed.

[Tanker572]

@patrickJMT how would you calculate the probability of rolling 2 dice and getting a sum of 5? so on and so forth, kina like getting a sum of this and that, these similar questions

[blimp99]

Left Handed (y)

[Ruth516]

I don't know when to use what method to solve problems. Eg. I have M&M candies. Yellow 20%,Red 20%,orange10%,blue10%,green10%­,brown 30%. If I got 3 chances to pick t the candies, what is the probability that they all are brown. 2. the third one is the first one is red? 3. none are yellow? 4. at least one is green?

[MsHershay]

haha can't we make things easier? The probability of all things to happen is 50%.

There are only 2 outcomes, 1) it happens 2) it didn't happens.

Example, probability of the red ball being drawn= 50%

Outcome 1) Red ball drawn 2) Non-red ball drawn

[patrickJMT]

@MsHershay really?

[Petematrix]

@patrickJMT By her logic there's a 50% chance that I'm going to get struck by lightning in the next 10 seconds, after all, it'll either happen or it won't ;o)

[slovakmath]

@MsHershay you have such a sad and simple mind....the probability of events happening are almost never 50 percent...its only 50% when there are only 2 choices and the chance for each choice are equal. rarely are there only two choices, and when there are only two choices the probability is again rarely equal for each option

[blo0oming]

@MsHershay No. Because given probability; If you have 7 white socks and 7 blue socks, how many socks must you draw to make a pair? 2 is not correct...

[thecapone45]

@MsHershay VERY good logic man...

-_-

[sunslap]

@MsHershay that wouldnt be very officiant. What if your dealing with something like a deck of cards, what is the chance of you pulling a heart? 1/4, what about a 5 of hearts? 6 of clubs etc? Apply this logic to something that isnt based off the absolute of it happening, or not. A meteor is flying aimlessly through our solar system, what are the chances of it hitting earth or not? 50%? No I dont think that works in most cases at all, unless you'r looking to do 100000 times the math.

[PLdrummer]

8:07 creepy voice "it would be!"

[hgfjyrdetryu]

omg this person is left handed!!!

[KidStarburst7]

You have a skill at explaining. Much thanks. 

[rajkamalraj2007]

left handed peoples generally more intelligents.....y

[BurnKilluminati]

my teacher is a dead fish when she teaches, thank god for youtube

[Sarz366]

somebody ! where did the 28 come from ??? it was so fast with no explanation :P

[MegaMcSpicyyy]

@Sarz366 28 is the number of days in the month of february

[SiliconPirate]

Leap years occur because contrary to popular belief... there is not 365 days in a year.

There are 365.25 days in a year. (because solar years are longer than calendar years by 6 hours) We just round down to 365 and add one day every 4 years to make up the lost difference.

ie: .25 x 4 years equals 1 day

[krillansavillan]

great refresher!

[FibonaziProductions]

Brilliant :). All confirms what I'd worked out about probability - which I'm happy about :D. I think of the quick way of calculating probability as the number of variables to the power of the number of combinations. So, for a bike padlock, for instance, there are four rings, or four combinations, and numbers from 0 to 9 on them, so 10 variables. The probability is then 10^4.

No. of variables ^ no. of combos is a simple formula that I can remember easily that is extremely useful :).

[nahangma]

THANKS A LOT.. HELPED A LOT... :)

[roozterchick]

Just to let you know Patrick, I consider myself the worst person when it comes to Math.. That's why I keep delaying on taking Math subjects until I have to really take them now since I'm done with other minors...:D

Anyway, I 1st took Algebra last, last semester (??) and I got and "A" ^_^ (Yey for me!) .. And it was because I studied and your vids HELPED ME A LOT!!

Now, I'm taking Statistics and Probability hasn't really sink in to me yet.. 1 reason, my prof Lectures/speaks like a machine g

[roozterchick]

@roozterchick cont: like a machine gun :D But she's just really hyper and enthusiastic about teaching Statistics that's why.. ^_^

So for this semester, I'm going to try again for "A" :D And I'm going to watch all the vids I can find for Statistics and hopefully, my odds of getting an A will increase :D

[FibonaziProductions]

@roozterchick - Gratz :D.

[SonyCamry]

why are there only 10 outcomes at the start? it could go up to 100? please reply

[FibonaziProductions]

@SonyCamry - No, he means specifically the last digit. Like the last digit in 4582 is 2, and there are ten different outcomes as to what that end digit could be.

[jwmcmac]

you are considering that each day is a likely as the next . . . but, depending on the culture . . . it is more likely to be born 9 or 10 months after Christmas/NewYears . . . and each day would have to be weighted according to customs and circumstances . . . etc . . . but . . . all things 'days' being equal . . . then the simple probability would be 28/365 in a non-leap year . . . just as you were demonstrating.

Good statistics is simple . . . but subjectivity complicates the simple.

[jwmcmac]

@jwmcmac Thanks for your great lessons, Patrick.

[hoybezy]

thank you my teacher sucks

[janinelovesmusic]

thanks... i'm crossing my fingers for my test tomorrow.

[Petecpa]

Very Interesting

[corleonecico]

Can you do more videos of statistics and probability???

[paulver00]

Hi Patrick. First of all, thanks very much.

I have a question. The coin has one head and one tail, so if you flip it three times the possible outcome is 2*2*2, as you did.

But if the coin had six sides(like a dice), It would be a multiplication 6*6*6 or the possible outcome would be a factorial 6!*6!*6! ? Since 2!*2!*2! is the same thing as 2*2*2, I got confused about how it would work out for number of sides > 2

[NinjaXSong]

@paulver00 look:

For any n flips of a coin, the number of outcomes is 2^n. This is because the first flip can be either 2 sides, then the next can also be 2 sides, etc...

Now, for k heads:

There are only n pick k times that you can get this. This is also a combinatoric question, since you must pick all outcomes with the k heads, which will be n pick k. ( i hope you can see that). So, dividing, we get (n pick k)/(2^n).

[gennkill]

thanks but i wonder whats the probability of my passing my test tomorrow! xD

[patrickJMT]

@gennkill if you dedicate the test to patrickjmt, you will be .00001% more likely to pass the exam!

[gennkill]

@patrickJMT umm... thats good right?

[gennkill]

@patrickJMT i pased! thanks!!!

[patrickJMT]

@gennkill sweet, congratulations : )

[MrinalChoudhary]

ok..the main reason that february has 28 days because it take 365 days and 6 hours for earth to complete one revolution around the sun..so february has less number of days so as the year does not have more than 365 days...but after every four years the extra 6 hours makes a day (6*4=24)..so a day is added to february to balance the 6 hours and thus the leap year..anyways..nice vid!!

[ZARALiCiOUS007]

A widely believed--but possibly erroneous--story has it that February is so short because the Romans borrowed a day from it to add to August. August was originally a 30-day month called Sextilis, but it was renamed to honor the emperor Augustus Caesar, just as July had earlier been renamed to honor Julius Caesar. Naturally, it wouldn't do to have Gus's month be shorter than Julius's, hence the switch.

[patrickJMT]

@ZARALiCiOUS007 interesting story! when do i get a month of the year named after me? it will have 200 days in it!

[joshua54321]

@patrickJMT hahaha!!!! me too!

[BlackJavaBean]

So the key thing that I got from this video is that, probabilistically speaking, folks born in February are better than everyone else because there's less opportunity. j/k. Thanks for the clear explanation.

[gemglass88]

Thank you. Very helpful.

[MaraimH]

Great way of explaining things. Thanks for uploading! :)

[sanjayudasi]

nice guide....tx

[candylopez1347]

Thank you sooo much :) my integrated algebra test is tomorrow and this helped me alot alot :} tytyty!!

[purpsmoka]

Great video fellow lefty. I have my stats final tomorrow and even though the material is not difficult, videos like this help sharpen the senses

[HeadShot360IN]

thanks so much, i have a really bad technique math teacher as my sub since my regular one has been off for a year and a half on mat leave. Thanks so much

[theajmeraful]

Hey, your video's really help me understand 10th grade math. Where do you teach?

[supermadcrazy]

it really helpin u er a good teacher buddy

[Ramiromasters]

At least this guys makes very simple examples, my statistics teacher was a savage! a monster...

[nttt7898]

ohhhhhh thanks . Now i understand , that is always find the outcomes . U mupltiply it like u multiply EXPONENT !

[stealthdoughnut]

If you think of all the police officers with 911 as their "other" phone number, there are a slightly disproportionate number of phone numbers that end in 1. And what if they work at directory assistance? :D

[Mexecution19]

exellent teacher thanks so much from mexico

[loveleeSue]

that was helpful. thanks for your nice video :)

[alexe610]

very good teacher , thank you so much from France.

[sullivanseven]

Now I realized that you are a magician! At 5:29 there is no arrow, but at 5:30 it magically appears! (beside 1/32)

[HAZhost]

you forgot one possible out come what if the next person you meet has no cellphone

[horneydannny]

Great tutorials, keep them coming, for I have a maths exam in June : )

[f1n3e]

Thank you man! this video helped a lot.

[Tydy01]

Thank God for these video's! This is the only way I'm passing stats.

[INFOMASTER666]

you helped me a lot, thanks so much, i'm addicted to those videos :D

[DoctorPlausible]

An interesting one: The probability that the next person you meet has an amount of money is his pocket that starts with the digit 1 (say, $14 or $163) is greater than the probability that this amount starts with any other digit. This has been proven to be true. I'm not kidding.

[masterchanges]

exercuse me...

about the person that we meet with the LAST number 5...

that what you did is the probability that the next man will have A NUMBER 5 IN HIS PHONE NUMBER...NOT THE LAST...Think about it you ve get 10 percent that the man will have 5 in the end of his number..It is impossible...the right answer is 0.01..commet please

[goc9999]

wrong...

IE. if phone nmbr. has 3 digits, the probab. would be (10*10*1)/(10*10*10)=1/10

[ynacutekristinakulet]

I really think it is correct (the answer showed in the video), would you elaborate more on your answer? how did you get it?

[TheWBarry]

@masterchanges: you are wrong -- a phone number CANNOT have 3 numbers as the last number. That just dont work.

[Theauthenticmindset]

i always get heads ;)

[janbaz125]

Bob arrives to work on time with probability 0.70, while Caroline arrives on times with probability 0.80. The probability they both arrive on time is 0.60.

1)What is the probability that at least one of them arrives on time?

2)What is the probability that exactly one will arrive at work on time?

3)What is the probability that neither one of them will arrive to work on time?

[MAGIC991000]

?????????????????????/

[Prisoner7777]

YOU ARE LEFT-HANDED

[Sorrow707]

@Prisoner7777 apparently left handed people are agents of the devil, that's why 1 in every 10 people is left handed!!

[laurencegill]

my brain hurts

[TehCybernerd]

question! could we potentially know the result of the coin toss definitively, if we know all the variables and constants influencing how it lands? the downwards pull of gravity... the weight of the coin... the force and direction in which you flip the coin (which is really what changes)... etc?

the side the coin lands on is more a a question of the physics involved, isn't it? only we can't predict the variables...

[jediforcecny]

Help!! I'm a bartender in a local pub to work my way through school and (don't ask how it got brought up) but I've been arguing with a patron for two solid weeks that the probability of flipping a coin twice and getting heads both times is 1/4. Easy enough right? Not for him apparantly. It has annoyed me to no end. His basic argument is this. After flipping the coin once if it ends tails the condition is not met. thus (and I know it's insanely wrong) your odds are 50/50...help me!!!

[MrMorken]

Both of you are right, but it depends on what event you look at: If you look at the series of flipping the coin twice, then the probability of that happening with the same result is 1/4. If you look at the probability of flipping the coin once, then it is 50/50 or 1/2.

[jediforcecny]

BUT THAT'S NOT THE QUESTION! The question is the probability of flipping a coin TWICE and it being heads BOTH times. If the question was, what is he probablility of each flip..yeah 1/2. But that's not the question is it? Two head in a row from the beginning. 1/4. God, this is getting even more frustrating.

[MrVerruckter]

good job ;)

[Treseler7790]

I figured out the coin one relatively fast, rather than doing all the math.

Chance to land a head is 50%, so with that in mind...

Imagine you flip the coins and land on heads every time, and when you do, you drink half of a full can of pop. You drink half (50%) if you get heads. Another half (25%) if you get heads again. And another half (12.5%).

12.5(8) = 100

[jbenlez555]

or you would do the inverse of 2 to the power of n, with n being the times you flip the coin.

[turkeyman64]

My logic is that the inside of the outer parenthesis is what it is because there is a 9/10 chance that there will be a 50% chance of getting a head or ("or" my stats teach told me means add) there is a 1/10 chance that there will be a 100% chance of getting a head. So now that we have the probability of getting heads on one flip we need that 5 more times, so we need to flip a head and a head and a head and a head and a head ("and" my stats teacher tells me means multiply) there for i get ^5.

[turkeyman64]

I have a conditional probability problem that another probability youtuber has done that i am having trouble with how he got the answer. He asks, "if you have a bag filled with 9 regular coins and 1 double sided head coin, what is the probability of getting all heads for 5 flips. I thought the equation would end up being ((9/10)(.5)+(1/10)(1))^5. My next comment will explain my logic. his answer is somewhere around 70% but mine is near 3%, tell me if and if so why im wrong.

[mahlerite]

Your method and reasoning is correct, turkeyman64, and my answer in exact form is consistent with your answer in exact form.

By independence and the addition theorem of mutually exclusive events, I evaluate ((9/10)(1/2)+(1/10)(1))^5 = ((9/20)+(1/10))^5 = (11/20)^5. This gives about 5%, though, not 3%, so your rounded answer is slightly off.

[turkeyman64]

yeah sry i was thinking about the probability of getting 5 heads without the trick coin sry. Thank you!!!

[terrywoodinc]

thank you patrick. there's a chance i can pass my exam i i keep on watching your videos...

[Aerithiku]

Thank you so much for making this video :) it clarified some things that I was questioning about~

[kevin1232541]

cool vids man

[fg1i]

Taking the leap-year in consideration.

A year averages 365.25 days - - (365+365+365+366)/4

February can have 28.25 - - (28+28+28+29)/4 days.

That's 113/1461, or 7.73443%

0.0631% difference if you don't take the leap year in consideration.

[umezar]

Great JOB.............I PAT ur BACK..........PLZZZ PUT ON MORE PROBLEM AND SOLUTION VIDS OF PROBABILITY.THNX ALOT

[Blaccluv]

daz actcully alsome nojoke thanks

[crucio01]

No person you meet will give you their phone number nerd!

Just kidding mate, nice guide :p

[patrickJMT]

this coming from a person who has 'runescape' videos on their channel, loooooooool : )

[shaochiavang]

You have 3 doors,

you need to pick 2 out of 3 doors without hitting a X that is mark behind the door to win $10,000,you pick the first door and there is no X, now there are 2 doors left, one with a X and one without a X, what is your probability of hitting a door without a X?

[ophcrack2008]

runescape is good, im called Nick00179...Great guide

[frankandgang]

@patrickJMT That's fucking funny. You videos are sick

[TheIrishcircusgirl]

@crucio01 i would totally give him my phone number..now get back to your runescape..good boy.

[Kimidoki]

i'm also glad someone pays attention in math class ^0^

[patrickJMT]

it was not me... not til i got to college at least!

then it was time to act like an adult and take possession of my education!

[Kimidoki]

you're so smart ;_;

[xenon1987]

Thanks for these. I'm long out of school but I still like to learn all of this stuff. I was probably taught all this but forgot it all. Simple even for me :P

[smerrigan]

so according to 28/365 for feb its .076%? thats a pretty high prob?

[patrickJMT]

why is that high?

[QuikSand9]

are you sure it isn't .0767% ???

[patrickJMT]

it should be 7.67%....

[cuvanito305]

WOW!!! thanks bro i got a 98 on my math test thanks 2 u !!! THANK YOU!!

[patrickJMT]

nah! you did it! congrats!! i maybe help explain something, but you have to understand it : )

[iam2coo4man]

im doing math hw right now and its helping me so much thank you a lot.

[patrickJMT]

perfect! happy to help

[Bale365]

neat!

[HappyChemicals]

i like your voice and the way you explain things

[patrickJMT]

thanks and thanks : )

[DrLsw]

is there a formula for finding the outcome with only having the probability?

can you find the 5 with only having 1/32?

[schoolrocks20]

Thanx dude....I'v always hated Probability but now i think i can get that D grade replaced by just retaking that course. you are way better than my previous teacher.

[patrickJMT]

glad that the vids help! : )

[Waranle]

Thank you so much, can you plz do more videos about this subject, Thank you alotttttttttttttt

[patrickJMT]

i will most likely make some more probability videos today!

[charcoalfilter1101]

Thank you so much!!!!

[patrickJMT]

no problem! about to make some follow ups to this right now! how to calculate 'and' , 'or' and 'at least one' statements!