If there are on the average one percent lefthanders estimate

If there are on the average one percent left-handers, estimate the chances of having at least four left handers among 200 people. You can assume mutual independence. Hint: use the Poisson approximation!

Solution

X - no of persons having left handers.

Parameter = mean = np = 200(1%) = 2

Hence X follows a POisson distribution with parameter 2.

P(X>=4) = 0.1429