Elementary probability question: dice roll

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Mathman2013
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Homework Statement



Lets say you role a single honest dice 12 times. Where succes is either if the die shows 4 og 1 eye.

My question is what is the probability of sucess or failure?

Homework Equations

The Attempt at a Solution


Is it binomial or conditional probability?
 
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You roll one die 12 times if the die shows either 4 or a 1 it is success if it shows non 1 or non 4 for the remaining rolls then its a failture.

What is the probability of success or failure during the 12 rolls?
 
So is it a success if we get a 1 or 4 on the first roll (not needing to roll anymore)? Is it also the same success if we fail 11 times and roll a 4 or 1 on the last roll?

If that is what you want, then you can do something like this: (prob of NOT rolling 1 or 4) AND (prob of NOT rolling 1 or 4) AND . . . AND (prob of NOT rolling 1 or 4).
Turn each of those AND's into multiplication, and assign a number for (prob of NOT rolling 1 or 4), and you have the probability that it will fail (Not rolling a 1 nor a 4 in 12 rolls).

Once you have that, calculating probability of success is straightforward.