Question

the two - way table shows the results of a recent study on the effectiveness of the flu vaccine. what is the probability that a randomly selected person who tested positive for the flu is vaccinated? pos. neg. total vaccinated 465 771 1,236 not vaccinated 485 600 1,085 total 950 1,371 2,321 $\frac{465}{2,321}$ $\frac{465}{1,236}$ $\frac{465}{950}$ $\frac{465}{485}$

Explanation:

Step1: Identify relevant values

We want the probability that a person who tested positive for the flu is vaccinated. The number of vaccinated - and - positive people is 465, and the total number of positive people is 950.

Step2: Calculate probability

Probability = $\frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}}$, so the probability is $\frac{465}{950}$.

Answer:

$\frac{465}{950}$