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Iosif Pinelis
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The probability for the experiment of rolling two different colored dice is $$\frac{162601421574468954588}{2^{2\times36}}\approx0.0344322.$$


Indeed, for the set $[36]_0:=\{0,\dots,36\}$, let $T$ denote the set of all triples $(m,n,k)\in[36]_0^3$ such that $mn=36k$.

Let $I$ denote the set of all pairs $(a,b)$ of subsets of the set $[36]_0$ such that $a$ and $b$ are independent. Then $(a,b)\in I$ iff $(|a|,|b|,|a\cap b|)\in T$, where $|\cdot|$ denotes the cardinality.

For any given $(m,n,k)\in T$, $$N_{m,n,k}:=\big|\{(a,b)\in I\colon (|a|,|b|,|a\cap b|)=(m,n,k)\}\big|=\binom{36}m\binom mk \binom{36-m}{n-k}.$$

So, the probability for the experiment of rolling two different colored dice is $$\frac1{2^{2\times36}}\sum_{(m,n,k)\in T}N_{m,n,k} =\frac{162601421574468954588}{2^{2\times36}}.$$

Iosif Pinelis
  • 127.7k
  • 8
  • 107
  • 229