4 At a parcel delivery company it is known that the probability that a parcel is delivered to the wrong address is 0.0005 . On a particular day, 15000 parcels are delivered. The number of parcels delivered to the wrong address is denoted by the random variable \(X\).
- Explain why the binomial distribution and the Poisson distribution could both be suitable models for the distribution of \(X\).
- Use a Poisson distribution to find each of the following.
- \(\mathrm { P } ( X = 5 )\)
- \(\mathrm { P } ( X \geqslant 8 )\)
You are given that 15000 parcels are delivered each day in a 5-day working week. - Determine the probability that at least 40 parcels are delivered to the wrong address during the week.
- Determine the probability that at least 8 parcels are delivered to the wrong address on each of the 5 days in the week.