A pharmaceutical company conducted a study to evaluate the effect of an allergy relief medicine; 250 patients with symptoms that included itchy eyes and a skin rash received the new drug. The results of the study are follows.
90 of the patients treated experienced eye relief, 135 had their skin rashes cleared up, and 45 experienced relief of both itchy eyes and skin rash. What is the probability that a patient who takes the drug will experience relief of at least one of two symptoms?