An SRS of 100 flights by Nite-flite Airlines showed that 64 were on time. An SRS of 100 flights by Waxwing Airlines showed that 80 were on time. Let pN be the proportion of on-time flights for all Niteflite Airline flights, and let pW be the proportion of all on-time flights for all Waxwing Airlines flights. Is there evidence of a difference in the on-time rate for the two airlines