probability

[kind mulch]

i forget what to do for this but i know its simple i jsut cant brain

[flat skiff]

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[lucid bear]

For the second one you can use binomial distribution.
As for the third... Well, if you throw a lot consecutively, you will probably get tired, which will decrease your probability of success.

[kind mulch]

what is binomial distribution

im pretty sure i missed that in class and its on our mock tuesday

[lucid bear]

Suppose we have n independent events, each with probability of success p.
Then the number of successes follows a binomial distribution: X ~ Bin(n, p).
Its PMF is:
p(k) = C(n, k) p^k (1 - p)^(n - k), k = 0, ..., n
Here C(n, k) = n!/(k! (n - k)!) is the binomial coefficient.

So, in your case n = 3, p = 7/10 and you need to find P(X = 2), which is p(2) using the PMF.

[kind mulch]

Ohhhhh

that makes sense

thank you

[lucid bear]

You're welcome!

Actually, I can share a table with some of the most common distributions if you're interested.

I made it quite a while ago.

[kind mulch]

Sure

would help with my study

[lucid bear]

Here you go. Too big for a picture, so a PDF.
If you notice any mistakes, please notify me! I've checked it multiple times, but stuff can happen.

[kind mulch]

i have a question

would it be easier to do a bernoulli trial

for this

[lucid bear]

Well, binomial distribution is the sum of Bernoulli distributions anyway.

[kind mulch]

I see

so this should be correct right?

[lucid bear]

You shouldn't write a horizontal line when writing a binomial coefficient.

Other than that, yes.

[kind mulch]

why not

[lucid bear]

Well, that's just how it's written, without a horizontal line.

Otherwise it just looks like a fraction.

[kind mulch]

Alrightt

tysm

[lucid bear]

You're welcome!

[kind mulch]

+close