following the agreed upon logic: P[no fish in 2 hrs] = 1 - P[fish in 2 hrs] and then use Markov for the P[fish in 2 hrs] term to get 1 - (P[X>=2] <= E[X]/2). But this gives us a P[no fish in 2 hrs] >= 1/2, which is a lower bound, not an upper bound. This method seems right, but it doesn't answer the question exactly... Any thoughts?