Suppose a disk is expected to fail in 1 to 2 years. If the failure date ? is as likely to be in any sub interval as any other of the same size, what sort of random variable is ?? What is P(? > 1.5)? Solution it is uniform distribution where x belongs to [1,2] a=1,b=2 x=1.5 P[X>1.5]=(x-a)/(b-a) =(1.5-1)/(2-1)=0.5.