Question 1181903
There are 0.2 errors per page as the mean.
That is the Poisson parameter (this kind of problem is Poisson--mass function, counts proportional to number of trials, theoretical possibility of infinite numbers of errors per page)
p(3)=e^(-0.2)*0.2^3/3!
=0.0011 or 0.001
Also 2ndVARSpoissonpdf(0.2,3) ENTER