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  "body": "\n## Definition\n\nLet $\\Omega$ be a nonempty [[finite set|0BBTH3YSZA]] of equally likely outcomes.\nThe classical probability of an event $A \\subseteq \\Omega$ is\n$$P(A) = \\frac{|A|}{|\\Omega|},$$\nthe number of favourable outcomes divided by the number of all outcomes.\n\n## Remarks\n\nThis $P$ is a [[probability measure|0VGMEBVW1M]] on the power set of $\\Omega$, the uniform probability on $\\Omega$. Each outcome has probability $1/|\\Omega|$.\nFor two rolls of a fair die, the probability that the sum is $7$ is $6/36 = 1/6$.\nClassical probability turns a probability problem into a counting problem. Binomial coefficients and the rule of product often give the counts.\nThe definition is circular as a foundation, since \"equally likely\" already uses probability. It also does not apply to infinite sample spaces.\n\n## Explanations\n\n### L1 human\n\nWhen all outcomes have the same chance, a probability is a fraction: good cases over all cases.\nA fair die has $6$ faces and $3$ of them are even, so the chance of an even number is $3/6 = 1/2$.\n",
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