Expectations

Discrete Mathematics Level 4

You roll a standard six-faced-die and get \(n.\) Then, you roll it again until you get a number greater than or equal to \(n\).

The expected number of times you need to roll your die (after the initial roll) is of the form \(\dfrac{A}{B}\) where \(A\) and \(B\) are co-prime positive integers.

Find \(A+B.\)

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