Die rolling probability | Probability and combinatorics | Precalculus | Khan Academy

We're thinking about the probability of rolling doubles on a pair of dice. Let's create a grid of all possible outcomes.

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[violinplayer]

OMG, I actually understood that problem after he explained it! The problem with math is that you actually have to understand the way the problem works (you can't just memorize it), and that's the reason math has always been difficult for me...

[VndNvwYvvSvv]

Illustrative, but definitely the hard way to do it. If you aren't predicting the odds of both being one specific number (both 1s predicted, or both must be 4s), then the first die doesn't matter. You only care that the 2nd die matches. That's a 100% probability for the first or actually just ignore it, and dthe 2nd is merely 1/6. Same answer, much elss thinking and work.

[ToastedSynapseGaming]

They would fail you if you did something like this in an exam. ANYBODY can count. I was looking for a formula. Are you expected to create a table for the Probability of getting a Sum of 20 with 6 sided dice, for examole? There are many problems and there is a formula with Combinations, but I can't find it. That's what I was searching.

[bobm]

well you know the first roll has to be a number from 1 to 6 and so the second number has a 1/6 chance of being that same number... what was point of doing the rest of it lol

[sportgaming]

Thank you! I had a math problem on my test that didn't make sense so I purposely didn't finish my test so I could watch a video on how to solve it then solve it the next day, ;3

[sleepingyoongi]

Thanks it helped me out on my remote learning!

[orangecaprinun]

But how do we do this problem through permutations/combinations? which of the two is it even?

[oladiedoo]

Just wishing the same question comes in exams

[JR-tevs]

What if you have to answer it using fractions? like for example..
What is the probability of getting "3"
from the rolled dice?
would it be 1/6? please answer asap☝

[navajohnny]

I paused to work ahead and repeated the 5 also. 🤣🤣

[leanswagger]

Hey I have a question.

When rolling 2 dice, why is 7 the most likely sum of both of them?

The outcomes to get a 7 are - (1, 6), (2, 5), (3, 4), (5, 2) and (6, 1)

To get a 6 - (1, 5), (4, 2), (3, 3), (2, 4) and (5, 1)
My question is, why isnt there another (3, 3) in the pprbability pf getting a 6, as the die is indipendant from the other so why cant doubles be counted in prpbability, therefore increasing the chances of getting a 6?

[okwtf]

I rolled 6 doubles in a row last night I'm just trying to figure out the chances of that

[DustinStetler]

don't really need math for this as rolling the second die has nothing to do with how the first die rolled. you'd be implying that the outcome of the first die has an effect on the second roll (superstition). every roll has a 1/6 chance of landing on a number, no matter how many dice are rolled.

[SylkaChan]

Since its true that rolling two sixes or any number is only 1/36, you could use this all the way to make a theory of the probability of the multiverse. To acheive rolling ten 20s on 10 twenty sided dies only once is 1 in ~10 trillion.

[unlimitedpower]

This is wrong. The correct way to do this is 1/6 * 1/6 = 1/36

[kimryanpomar]

Find the probability of rolling triples on three six sided dice.
anyone?

[Hanyamanusiabiasa]

Can you make this video but with 4 dice?

[annl]

But if there are two dice, shouldn’t there be 12 favourable outcomes? As in one probability being 1 on one die and 1 on the other and the second probability being 1 on the other die and 1 on the first, you know? That’d be two ways of getting each double.

[LurkingVoltage]

If you roll a d6 once the average roll is 3.5.
If you roll a d6 three times and take the middle die result, what's the average on that number? Is it still 3.5?
Example you roll 3d6 result is 1, 4 and 6, so the middle here is 4.

[HumanRightsEveryone]

So rolling doubles is basically the inverse of rolling 7? Same odds, opposite slope.