Ever-so-forgetful Mister H has n keys in his key-ring: only one fits the lock in his door, and Mister H has no idea which key it was. Let X be the order number of try which unlocks the door. Calculate the probability mass function and cumulative density function of X, given that Mister H chooses the keys randomly and (a) remembers the keys he has tried, (b) does not remember the keys he has tried.

Ever-so-forgetful Mister H has n keys in his key-ring: only one fits the lock in his door, and Mister H has no idea which key it was. Let X be the order number of try which unlocks the door. Calculate the probability mass function and cumulative density function of X, given that Mister H chooses the keys randomly and (a) remembers the keys he has tried, (b) does not remember the keys he has tried.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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