! ! The first eight take three, and the remaining five take three together. Let's consider the simple situation first. The balance is even, indicating that the remaining two are defective.
! ! ! Take 1 from the weighed 1, and take1for the rest. You can judge which one is defective after weighing.
! ! Going back to the case where three out of eight are taken and three out of the remaining five are weighed together, the result is not flat. At this time, if the square height of three of the remaining five is taken, it means that the defective product is heavier than the qualified product, and if the low product is lighter than the qualified product, the two situations are the same, so it is assumed that the defective product is lighter, which is convenient for later analysis.
! ! ! Take three parts that may be defective and put one on each side of the balance. If it is flat, it means there is a defect. If the height of 1 is 1, the one with the lowest height of 1 is defective (analyzed above). (After explaining the situation at the beginning)
! Let's go back to the situation where there are four pieces on each side of the balance. If the balance is uneven, (the situation of left high or left low is the same, only the situation of left high). Now, all the parts on both sides are numbered, and the left side is set to 1. 1.65438, 1.2, 1.3,1.4,65438.
! ! Take a part that has been identified as a qualified product and set it as X. Now put X, 2.3, 1.4 on the left, 1.2, 1.3, 2.4 on the right, or consider from a simple situation. The balance is flat, indicating that the defective products are at 1. 1, 2. 1, 2.2; if it is 1. 1, the defective products are heavier; if there are defective products at 2. 1, 2.2, the defective products are lighter. (As mentioned above, it is explained by the situation of left height)
! ! ! Put 2. 1 and 2.2 on one side of balance 2. If it is flat, 1. 1 is defective; If it is not uniform, it means that there are defects below (as explained earlier, there are defective products in 2. 1 and 2.2, and the defective products are lighter).
! ! Put x, 2.3, 1.4 on the left and 1.2, 1.3, 2.4 on the right. If the left side is still high, it means that1.4,2.4 there are defective products where I haven't moved. Take a part that has been determined to be free from defects and weigh it with 1.4.
! ! If you put x, 2.3, 1.4 on the left, and 1.2, 1.3, 2.4 on the right, it becomes lower to the left, which means that I moved to 2.3, 1.2, 1.3.
! ! ! Put 1.2 and 1.3 on one side of balance 2. If it is flat, it means that 2.3 is defective; If it is not uniform, it means that it is high and defective.
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