A product is produced from three factories A, B, and C. At Factory A, the percentage of defective products produced is 5%. At Factory B, the percentage of defective products produced is 4%. At Factory C, the percentage of defective products produced is 2%. The shipment volume of Factory A is 20% of the total. The shipment volume of Factory B is 30% of the total. The shipment volume of Factory C is 50% of the total. At this time, calculate the probability that the defective product found in the market is a product produced in Factory A.