Question

A company manufactures caclculators in batchers of 64 and there is a 5% rate of defects. Find the probability of getting exactly three defects in a batch

Answer 1

I think I remember a bit of this from when we were generating OC curves for a math modeling project last semester.

In my notes there is the equation:
P(d)= (n!/(d!(n-d)!))*(p^d)(1-p)^(n-d)

It's assumed that the total lot is very large, so when you take n, the sample size, out doesn't change the remainder.

P(d)= prop of observing exactly d
number of defectives= d
random sample= n
p= fraction of defectives per lot.

Hope this helps