After a computer virus entered the system, a computer manager checks the condition of all important files. She knows that each file has probability 0.2 to be damaged by the virus, independently of other files. (a) Compute the probability that at least 5 of the first 20 files are damaged. (b) Compute the probability that the manager has to check at least 6 files in order to find 3 undamaged files.

After a computer virus entered the system, a computer manager checks the condition of all important files. She knows that each file has probability 0.2 to be damaged by the virus, independently of other files. (a) Compute the probability that at least 5 of the first 20 files are damaged. (b) Compute the probability that the manager has to check at least 6 files in order to find 3 undamaged files.

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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