Question

A fair, 6-sided die is rolled continually until two consecutive 6s appear. Find the expected number of rolls.

Answer 1

Answer: The answer is seven (7)

Explanation:

Instinctively we would expect the sum of a single die to be the average of the possible outcomes, i.e:

S= 1+2+3+4+5+6

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         6

= 3.5

And so we would predict the sum of a two die to be twice that of one die,  i.e we would predict the expected value to be seven(7)