In the question for

I can follow the working, but should it be "...probability that there will be at least

If not, what is the reason?

In the solution for

...2000e^-0.6 sigma (2=<k<infinity) 0.6^k/k!

This then changes to

...2000(1 - e^-0.6 - 0.6.e^-0.6)

What is the theory behind this change, and is there a reference in the manual?

Cheers,

Miles

**Ex 2.8**it says "Calculate the probability that there will be at least four months in which no accidents occur before the fourth month in which at least one accident occurs."I can follow the working, but should it be "...probability that there will be at least

**three**months in which no accidents occur..." ?If not, what is the reason?

In the solution for

**Ex 2.9**the calculation for E(Y) contains...2000e^-0.6 sigma (2=<k<infinity) 0.6^k/k!

This then changes to

...2000(1 - e^-0.6 - 0.6.e^-0.6)

What is the theory behind this change, and is there a reference in the manual?

Cheers,

Miles

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