Answer part a of the following question. Show work.

Let Y > 0 be a continuous random variable representing time from regimen start to bone-marrow transplant. Everyone does not survive long enough to get the transplant. Let X > 0 be a continuous random variable representing time from regimen start to death. We can assume X Y and model time to death as X Exp(rate = ) and time to transplant as Y Exp(rate = ). Where Exp(rate = ) denotes the exponential distribution with density f(z | ) = ez for z > 0 and 0 elsewhere - with > 0.

a.) Compute the probability that a patient receives transplant before they pass away (die) by integrating over the joint density fxy.