Shirley runs a real estate company. She counts the total number of flats that she sells everyday. Let X_t be the total number of flats she sells on day t (t=1,2,...,7), and let X be the total number of flats she sells for the week. Suppose X_t are independent and identically distributed Poisson distribution with expectation theta.
(Please see the attached file)
(a) Find the moment generating functions for X_1 and X
(b) Show X has a Poisson distribution with mean 7*theta