1. The problem statement, all variables and given/known data On average, 2 students per hour come into the class. What is the probability that the time between two consecutive arrivals is in the interval <10 minutes; 50 minutes>. 2. Relevant equations p(k)=P(Y=k)=((lambda*t)k*(e-lambda*t)/k! 3. The attempt at a solution I've tried using the Poisson distribution with k=2 t=40/60=2/3 and lambda=4/3 but the result is wrong. Thanks for helping!