2 votes 2 votes Answer is 50,700,551/10,077,696 ≈ 5.03 Do we need to take all X(R.V.): 1,2,3,4,5,6,7,8,9,10 cases or else Probability probability expectation + – Sahil Gupta asked Nov 25, 2014 Sahil Gupta 1.7k views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
Best answer 4 votes 4 votes 1 * P(first = 6) + 2 * P(second = 6) + ... 10 *P(first nine ! = 6) = 1 * 1/6 + 2 * 5/6*1/6 + ... + 9 * (5/6)81/6 + 10*(5/6)9 The first 9 terms form an Arithemtico-geometric progression and we can find the sum using the formula given here: https://en.wikipedia.org/wiki/Arithmetico-geometric_sequence Or, we can sum them individually. Answer comes out to be 3.0928 and adding the last term gives 5.03 Arjun answered Nov 27, 2014 selected Jul 12, 2015 by Arjun Arjun comment Share Follow See all 0 reply Please log in or register to add a comment.