4 Birds arrive at a feeding table independently, at an average rate
of six per hour.
a Find the probability that two birds will arrive in the next ten
minutes.
b Find the probability that I have to wait more than ten minutes
before the next bird arrives.
c Find the expected mean and standard deviation of the time (in
minutes) I have to wait for a bird.
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I don’t understand part c, surely if the time you have to wait follows an exponential distribution with X~Exp(10) where a bird comes every 10 minutes wouldn’t the mean be 1/10 and the standard deviation 1/10?