Skinny's Casino

by Neil Murrell & Joe McCrea

When three dice are rolled, one of the three returned values will always be between the other two (unless you get two values that are the same). The odds that your die's number lies between the numbers on the other two is 1/3, with a small correction to allow for multiple occurances of the same number.

The likelihood that three different numbers will appear is (20 * 19 * 18) / (20 * 20 * 20) = 0.855 The likelihood that your number is the middle of these three is one third of this, or 0.285.

It was pointed out in the forums that "between" can be ambiguous in meaning. In most instances it is exclusive (stuck between a rock and a hard place) rather than inclusive (just between you and me...), and this is the meaning that was adopted here.

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