Measuring activity of uranium in a Geiger counter pulses arrive according to a Poisson process with rate 2 arrivals per second. Measured plutonium the arrival rate is 5 seconds.
For 0.2 seconds if there were no arrivals, what is the probability that uranium was being measured?
I think such problems can be solved with the Erlang distribution or truncated Poisson,
is this correct, or how they do it?
Thank you very much