A box contains 20 balls 10 are yellow 6 are red and 4 are grey what is the probability of picking a yellow then a red ball without replacing the first

Empty box + box + empty box fill in the box is equal to 30 how

Which of the following expressions cannot be simplified to x – 2?

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)