XYZ Electronics Inc. purchases TV picture tubes from three different suppliers. Supplier A supplies 40% of the tubes, Supplier B supplies 35%, and Supplier C supplies 25%. 

Supplier A tends to have the best quality, as only 3.6% of its tubes arrive defective. Supplier B’ tubes are 4% defective, and Supplier C’s are 8.7% defective.

A defective picture tube was discovered in the latest shipment. What is the probability that it came from Supplier A? (round answer to 3 decimal places)