Angioplasty is a medical procedure in which an obstructed blood vessesl is widened. In some cases, a wire mesh tube, called a stent, is placed into the vessels to help it remain open. A study was conducted to compare the effectiveness of a bare metal stent with the one that has been coated with a drug designed to prevent reblocking of the vessel. A total of 5320 patient received bare metal stents, and of these, 841 needed treatment for reblockig within a year. A total of 1120 received drug-coated stents, and 134 of them required treatment within ayear. At the 0.01 significance level, test the claim that the proportion of patients who needed retreatment was higher for those who received the bare metal stents.