The exponential density function is p = lift/u$ H where t. is the time in minutes and p is the average time between successive events. The denite integral gives the probability that the lapsed time be fore the next occurrence lies between $1 and t2 units of time. Trucks arrive at a terminal at an average rate of 6 per hour (10 minutes is the average time between arrivals). a) If a truck has just arrived, nd the proba- bility that the next arrival will occur within 17 min