Although the detection system X and the detection system Y are based on different principles, they can detect all product defects, and they will erroneously eliminate 3% of non-defective products. Due to the high cost of erroneous elimination, two sets are installed at the same time. System and save money by simply eliminating products that both systems consider defective. The above discussion needs to be based on the following hypothesis. ['The loss caused by accepting a defective product is greater than the loss caused by eliminating a flawless product.', 'Regardless of which system is used, the second test only needs to test the products that have not been eliminated for the first time.', 'Among products in the same price range, System X and System Y are the least error detection systems on the market.', 'The 3% defect-free product incorrectly eliminated by System X is not identical to the 3% defect-free product incorrectly eliminated by System Y.']