N example 5.4 and exercise 5.5, we considered the joint density of y1, the proportion of the capacity of the tank that is stocke
d at the beginning of the week, and y2, the proportion of the capacity sold during the week, given by f(y1,y2)= 3y1, 0≤y2≤y1≤1, 0, elsewhere. a find the marginal density function for y2. b for what values of y2 is the conditional density f ( y1 | y2 ) defined? c what is the probability that more than half a tank is sold given that three-fourths of a tank is stocked?