A study of the time between random arrivals
To analyse how much time you expect between random arrivals, we can use the exponential pdf. The data is the number of counted ( such as hockey goals ) over a given time interval (in minutes). You can then enter a time of concern, and calculate the probability that the time between arrivals is < the time of concern.
Research the exponential distribution. Find out it's mean and standard deviation. Identify an integral for evaluating the probability calculated above.