For some fixed integer k the random variable X has probabili
     For some fixed integer k, the random variable X has probability mass function (pmf) given by  p(x) = {c(k - x)^2 for x = 0, 1, 2, ..., k - 1  0 otherwise.  Find the value of c when k = 10, 30, 100, Note sigma_r = 0^k - 1 p(x) = 1.  Find  P(X lessthanorequalto 5) and  P(3 lessthanorequalto X lessthanorequalto 8) when k = 10, 30, 100. Note P(X lessthanorequalto a) = sigma_x - 0^a p(x) and P(c lessthanorequalto X lessthanorequalto d) = P(X lessthanorequalto d) - P(X lessthanorequalto c - 1). 
  
  Solution
Value of k Value of C P(X<=5) P(3 <= X <= 8) 10 0.002597403 0.92208 0.361039 30 0.000105764 0.48176 0.3827599 100 2.96E-06 0.16888 0.158653
