The number of errors per 1000 words made by a particular typist has a Poisson distribution with a mean of 2.5. (a) Find the probability that, in a 4000 word script, there should at least be 14 typing errors. (b) Using a suitable approximation, show that the probability will be more than 25 errors in a 10000 word dissertation.

The number of errors per 1000 words made by a particular typist has a Poisson distribution with a mean of 2.5. (a) Find the probability that, in a 4000 word script, there should at least be 14 typing errors. (b) Using a suitable approximation, show that the probability will be more than 25 errors in a 10000 word dissertation.

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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