2nd grade math, the digital castle is the home of the wise old man, there are two gates with passwor

The code for the first door: 9

So the password for the first gate is 9

Code for the second gate: 495

This answer is untenable: 370-307 = 423 840-408 = 432 (4 + 2 + 3 = 9 instead of 18), 320-203 = 117 (1 + 1 + 7 = 9), 510-105 = 405 (4 + 5 = 9).

If the answer is 495, there is not a single counterexample.

The password of the first door is 9, because according to the law that the sum of the results of each equation is 9, and the password of the second door is 18, because according to the law that the sum of the results of each equation is the law of 18.

The code for the first door: 9

81-18=63 63-36=27 72-27=45 54-45=9 51-15=36 63-36=27 72-27=45 52-25=27 72-27=45 ……The sum of the numbers as a result of each calculation is 9

So the password for the first gate is 9

The code for the second gate: 18

730-037=693 840-048=792 320-023=297 510-015=495 972-279=693 963-369=594 321-123=198 981-189=792 972-279=693 954-459=495 ……The sum of the numbers is 18

So the password for the second gate is 18

First of all, I don't know how 495 is calculated, and secondly, the upstairs example is 370-307=423 840-408=432 (4+2+3=9 instead of 18), which is also not right, the question is to take three numbers to form the largest and smallest numbers, since you take the largest number, it should be 730, and the smallest composition should also be 37, not 370 and 307 730−37=693(6+9+3=18)。The latter counterexample should be 840 48 = 792 (7 + 9 + 2 = 18).

I think it's 9 and 99... The second question is a multiple of 99.

I think it's like this, we put it, their numbers are all reversed, so we can write any of them, we just don't have to exceed the numbers from 0 to 9.

730-307 does not conform to the maximum minus, these three numbers form the minimum number 037, which is 37,730-37 693,6+9+3 18

I also think the second question is 99

The password for the first door is 9, the code for the second door is 198, the order 987-789 198, 876-678, and so on until 210-012 198

Answer: The sum of each calculation is 18, e.g. 693,594,981,792 ,......

This answer is untenable: 370-307 = 423 840-408 = 432 (4 + 2 + 3 = 9 instead of 18), 320-203 = 117 (1 + 1 + 7 = 9), 510-105 = 405 (4 + 5 = 9).

If the answer is 495, there is not a single counterexample.

The first question is 9, and the second question is 18, because the number is the same as forever!

The difference between the second gate is a multiple of 99.

I don't understand the question and I'm still posting here,

The code for the first door: 9

81-18=63 63-36=27 72-27=45 54-45=9 51-15=36 63-36=27 72-27=45 52-25=27 72-27=45 ……The sum of the numbers as a result of each calculation is 9

So the password for the first gate is 9

The code for the second gate: 18

730-037=693 840-048=792 320-023=297 510-015=495 972-279=693 963-369=594 321-123=198 981-189=792 972-279=693 954-459=495 ……The sum of the numbers is 18

So the password for the second gate is 18

There are two gates with combination locks, the first door code prompt, choose any two different numbers from 0 to 9, form the largest number and the smallest number and subtract them, like the following to go on, you will find the password of the first door. 81-18 equals 63, 63-36 equals 27, 72-27 equals 45....The password of the second door hints, choose any three different numbers from 0 to 9, form the largest number and the smallest number and subtract them, like the following to continue, you will find the password of the second door.

972-279 equals 693, and 963-369 equals 594,..Ask for a password.

The secret of the first door is not 9

The secret of the second gate is 198 or 9, because the smallest result of the subtraction of these numbers is 198, and the result of subtraction is only 891,792,693,594,495,396,297,198, these numbers are symmetrical with 9, the ten digits are all 9, and the sum of the single digits and the hundred digits is also 9, so the secret may also be 9

However, the question stem is not clear, and it can only be associated, and the password is related to 9.

You're going to shoot the problem.,We don't have a math book for the second grade.。。。