There are two urns a and b. Urn a contains 2 red balls and 1 blue ball; urn b contains 1 red ball and 1 blue ball. An experiment consists of drawing a ball at random from urn a, noting its color, placing it in urn b, and then drawing a ball at random from urn b and noting its color. A random variable X is defined by assigning to each outcome the total number of red balls drawn. Find the expected value of X.