A fair die is tossed until six is obtained on it. Let X be the number of required tosses, then the conditional probability P ( X ⩾ 5 ∣ X > 2 ) is :

Question

A fair die is tossed until six is obtained on it. Let X be the number of required tosses, then the conditional probability P ( X &#10878; 5 &#8739; X &#62; 2 ) is :

Aicharya · Accepted Answer

P x &#8805; 5 x &#62; 2 = P ( x &#8805; 5 &#8745; x &#62; 2 ) P ( x &#62; 2 ) = 5 6 4 1 6 + 5 6 5 1 6 + . . . . . . . &#8734; 5 6 2 &#183; 1 6 + 5 6 3 1 6 + &#8230; &#8230; &#8230; . &#8734; = 5 6 4 &#183; 1 6 1 - 5 6 5 6 2 1 6 1 - 5 6 = 5 6 2 = 25 36

A fair die is tossed until six is obtained on it. Let X be the number of required tosses, then the…

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