1, each person has two hands, two people can add 20 at most, and each party gives three numbers: 0, 5, 10.

2. At the same time, quote a number greater than or equal to the number in your hand.

3. If the sum of both bids is equal to their respective figures, you win.

4. Calculate that the minimum number of quotations is 0, because both parties may be 0 and the maximum is 20, because both parties may quote 10.

Other guessing methods:

Counting in the order of natural numbers, 1, 2, 3, 4, 5, 6, 7, numbers ending in 7, such as 7, 17, 27, 37, are called Qi Ming, and multiples of 7, such as 14, 2 1, 28, are called dark seven.

From left to right, 1, 2, 3, 4, 5, 6, 7 (silent) and then reverse the order. The person named 6 should be followed by 8, 9, 10,1,12,/kloc.