Emily owns a small business selling used books she knows that in the last week to customers paid cash 13 customers use a debit card and 84 customers use the credit card based on these results express the probability that the next customer will pay with a debit card as a percent to the nearest whole number ​

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)