A company employs Andy, Barney, and Chuck. Andy fills 35% of orders, Barney fills 40% of orders, and Chuck fills 25% of orders. Now, Andy makes a mistake 4% of the time, Barney makes a mistake 3% of the time, and Chuck makes a mistake 6% of the time. If a customer discovered a mistake in her order, then what was the probability that Barney filled her order?
