A fast-food chain has collected some data on its operations for the following three random variables (data is in minutes for all variables): X= Arrival Time to Initiating Order Placement Y= Arrival Time to Completing Order Placement Z = Time from Order Placement Completion to Completed Order Delivered to Customer In addition, the model that seems to best fit the available data is of the following form: fxxzz(x,y,z)=(a+b)∗b∗c∗e⁽−ᵃˣ−ᵇʸ−ᶜᶻ⁾,0Find the marginal pdfs for X,Y, and Z.
