Chapter 5 Joint Probability Distributions and Random Samples

Ex.6 A bank operates both a drive-up facility and a walk-up window. On a randomly selected day, let X = the proportion of time that the drive-up facility is in use, and Y = the proportion of time that the walk-up window is in use. Suppose the joint p.d.f. of (X,Y) is given by

= 0 otherwise

1. 
   Verify that this is a legitimate probability density function
   
2. 
   Find the probability that neither facility is busy more than one-quarter of the time.
   

= 0 otherwise

Compute (a) p (X  Y) (b) p (X  a)

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