If we have a square with langth, say 1, and a circle in this square, then the probability a point, at random, to be in the circle is the area of the circle. But the amont of points in and out the circle is infty. Why? When you can define the probability as some measure over the space?]]>

An infinitesimal value.

well i dont know what you said, but yeh, the chances of just one point being inside the circle is infintisamely small, since the point can be anywhere in infinate space

]]>An infinitesimal value.

I THOUGHT THE SAME THING!!!

]]>What you must have is all four points inside the circle. Find the probability of any single point to be in the circle. Then raise that value to the fourth power.

For any "usual" set of numbers (naturals, integers, rationals, reals, irrationals, complex), this question doesn't really have an answer since there is an infinite amount of points. Same goes for any infinite subset of them. It only starts to have a value when you have points defined on bounded integers. Of course, then a circle doesn't make much sense, now does it?

]]>Any circle?

How do you define "random"?

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