Question

Nathan had an infection, and his doctor wanted him to take penicillin. Because Nathan’s father and paternal grandfather were allergic to penicillin, Nathan had a 75% chance of having the same allergy. The doctor performed a skin test to see whether Nathan would react to it. The test is 98% accurate. What is the probability that Nathan is allergic to penicillin and the test predicts it?

Answer 1

I'm not 100% sure but if there's a 98% chance that, if he is allergic, the test will be positive, and a 75% chance of being allergic, you could simply multiply 75% times 98% to get the probability of both events