Dependent probability introduction | Probability and Statistics | Khan Academy

Let's get you started with a great explanation of dependent probability using a scenario involving a casino game.

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Probability and statistics on Khan Academy: We dare you to go through a day in which you never consider or use probability. Did you check the weather forecast? Busted! Did you decide to go through the drive through lane vs walk in? Busted again! We are constantly creating hypotheses, making predictions, testing, and analyzing. Our lives are full of probabilities! Statistics is related to probability because much of the data we use when determining probable outcomes comes from our understanding of statistics. In these tutorials, we will cover a range of topics, some which include: independent events, dependent probability, combinatorics, hypothesis testing, descriptive statistics, random variables, probability distributions, regression, and inferential statistics. So buckle up and hop on for a wild ride. We bet you're going to be challenged AND love it!

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[Bioreactress]

Brilliant. I love the ethos of this channel. Thank you for all your hard work!

[ayeshamousumisinger]

Thanks for this video . It has been so useful for me

[dtawantawng]

I like math, I really do. But probability, or at least the way that it is taught and the examples that are used to demonstrate the concepts of probability, are so insipid and entirely uninteresting that I cannot for the life of me sit through and pay attention to one of these lessons. Is it just me or does anybody else share my sentiments?

[美麻-bb]

Thank you so much for creating videos such as these, I really appreciate you helping me and explaining in way that can make me understand better.

[almwaysa]

Answer to ur question:
3/5 * 3/5 = 9/25 =0.36 chance
on average $1*0.36 = 36cents :) which is higher than 35, so yes :)

[esmailiyou]

This guy is awesome. Makes you love the probability theories. Clean and understandable teaching. Thanks a lot!!!

[TasyaAdzkiya]

*From Gladwin* on the questions sections of Khan Academy:
Can anyone explain to me the last part on how I would get $0.30?

*From David Betzer* on the questions sections of Khan Academy:
Because the probability of picking the "winning" combination of two green marbles in a row is 0.30, you can expect to win the prize of $1 about 30% of the time on average. So, if you played the game many many times, the average amount of money you win per game (meaning the amount you win in total divided by the number of times you played in total) will be $0.30.

For instance, suppose you played 10, 000 times, you could expect to win the $1.00 prize about (0.30)*(10, 000) = 3, 000 times. So in 10, 000 games, you would win $3, 000 dollars. The amount of money you are winning per game is $3, 000/(10, 000 games played) = $0.30 per game.

[gondorious]

Had an exam on this yesterday, thanks Sal.

[priscilagudino]

I have the need to say, thank you so much. I finally understand.

[YoloAlf]

what if i told you would still play it.

[Roamer]

Nice interactive instruction Sal! I do not gamble much but sometimes unexplained magic can happen, but usually while I watch LOL

[shantanuverma]

Hands down! This is just mind blowing explanation

[honrilful]

(3/5) * (3/5) = 0.36, So sure, unless I have to replace it with a red marble (Which would definitely be worse than not putting a marble back in the bag (3/5) * (2/5) = 0.24).

[lawliet]

1:15 obviously fairly low stake casino🤣🤣🤣🤣🤣

[SirTrollsAlot]

Clear explanation of dependent probalility!! Good stuff

[amerhashem]

thank you for valuable information and great support videos. I am using your material to prepare for my GMAT

[markbro]

I think he means expected value of winnings (win $1.00 30% of the time and $0 70% of the time), not expected value of the gamble (-$0.35 70% of the time and $0.65 30%) or -$0.05 which is a negative expected value or on average you are going to lose 5 cents. Sort of the same thing Sal was saying just phrased a bit different.

[DavidDiez]

Great video (per usual), but shouldn't the title be "introduction to conditional probability"? Using non-standard terminology makes it a little confusing when integrating or referencing the videos with traditional courses.

[pandoradragg]

bro explained this better than my own teacher

[Liaomiao]

this going to be a set of videos on discrete mathematics and college level probability?