Statistics, Probability, OR equation

[Calculator14]

Homework Statement

An appliance store purchases electric ranges from two companies. From company A, 600 ranges are purchased, and 5% are found to be defective. From company B, 300 ranges are purchased, and 8% are found to be defective. Given that a range is defective, find the probability that it came from company A.

Homework Equations

(work shown below) use "OR" equation

The Attempt at a Solution

(600)(.5) - (300)(.8) = 60

 

[the_amateur]

your answer is wrong..

use bayes theorem