If the egg is 10 kg, it means that there is nothing wrong with the stall owner's weighing device, so if the baskets are weighed together, it should be 10.5 kg. But the result is 10.55kg, which shows that the weighing value of the stall owner's weighing device is greater than the actual weight value, and it can be judged that there is something wrong with the stall owner's weighing device.

Let's begin to explain teacher Zhang's judgment method.

There is something wrong with the weighing device, which has been determined. Now we need to determine the ratio of the weighed value to the actual value.

Teacher Zhang's basket weighs 0.5 Jin, but it is 0.55 Jin on the vendor's weighing instrument. That is to say, the vendor's weighing device will weigh about 10% more than the actual weight, so Teacher Zhang concluded that 10 kg of eggs is missing about 1 kg.

Note: 10% here is only an approximate value, not an accurate value.

Because the team needs to hope to adopt it as soon as possible.