Cost of Flying Listed below are costs (in dollars) of roundtrip flights from JFK airport in New York City to San Francisco. All flights involve one stop and a two-week stay. The airlines are US Air, Continental, Delta, United, American, Alaska, and Northwest. 30 Days in Advance: 244 260 264 264 278 318 280
1 Day in Advance: 456 614 567 943 628 1088 536

Anew test for ra is being developed. the test is administered to 750 patients with ra and 750 without ra. for the sake of the question, assume the prevalence of ra in this population is 50%. of the 750 patients with ra, 575 have a positive result. of the 750 patients without ra, 150 have a positive result. what is the positive predictive value of the new test? a575/(575+150) b. 600/(600+ 150) c. 575/(575+125) d. 600/(600+ 125)