In: Math
The probability density function of the random variable X is given by fX(x) = ax + 2/9 if 1/2 ≤ x ≤ 3, and 0 otherwise.
(a) Compute the value of a.
(b) Let the random variable Y be defined as Y = [X], where [·] is the “round down” operator (that is, for example, [2.5] = 2, [−2.5] = −3, [−3] = −3). Find the probability mass function of Y . (Hint: For Y to take value k, what values should X take?)
(c) Compute Var(Y )
I am confused with part B.