In a book of 520 pages, 390 typo
-graphical errors occur. Assuming Poisson law for the
number of errors per page, find the probability that a random sample of 5 pages will
contain no error.
The average number of typographical errors per page in the book is given by
"\u03bb = \\frac{390}{520} = 0.75"
Hence using Poisson probability law, the probability of x errors per page is given by:
"P(X=x) = \\frac{e^{-\u03bb}\u03bb^x}{x!} \\\\\n\n= \\frac{e^{-0.75} \\times (0.75)^x}{x!}"
The required probability that a random sample of 5 pages will contain no error is given by:
"[P(X=0)]^5 = (e^{-0.75})^5 = e^{-3.75}"
Comments
Leave a comment