An accountant who prepares final accounts for his clients. Work arrives at his office randomly at a rate of 12 per month. The times taken to complete the work form an exponential distribution with a mean of 2 days. There are 25 working days in each month.
I calculated $\mu=12.5$ $\lambda=12$ $p=(12/12.5)=0.96$. Is this correct Have I made a mistake?