What I was thinking is that I`ll calculate the p(d/+) where d is the disease and + stands for the tests giving a positive result. So p(d/+)=p(d intersection +)/p(+). Now this positive result could come from either test 1 or test 2. Ultimately after solving for the entire thing I get 5/13. Is my approach wrong? Should it be p(d/+ve)= p(t1). P(d/+ve and t1)+ p(t2).P(d/+ve and t2) instead?

Sreyashi , 7 Years ago

Grade 12