Alex and Brandon bought candy and popcorn at the movie theater. Alex bought 2 tubs of popcorn and 3 boxes of candy for $19.50. Brandon bought 2 tubs of popcorn and 5 boxes of candy for
$22.50. If all the popcorn costs the same and all the candy costs the same, how much did one tub of
popcorn cost?

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)