The local ymca has a ratio to 3:4 boys to girls at the beginning of the summer break. At the end of summer break the ratio was 5:2 if the ymca began the summer with 105 total children how many boys where enrolled at the end of summer break

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)