By : **ylq**

Everyone must have played the game of 24 points. Its gameplay is very simple: first prepare 10 digital cards of 1~10 Carton Of Cigarettes, then draw four of them Buy Marlboro Cigarettes Online, add, subtract, multiply and divide these kinds of arithmetic symbols, and put these four The card is made up of numbers 24. This kind of gameplay is convenient, simple, and fun. If you practice regularly, you can open up our thinking anay, when I finished my homework, I played a 24 o'clock game with my mother. We played a lot of fun. But a problem, but it is difficult for me to live: 1, 2, 6, 8. I couldn't think of the solution to this problem. When my mother saw that I hadn't thought about it for a long time, I told me the answer: "(1��6)��(8��2), do you say that it is equal to 24?" I suddenly realized. After that, my mother gave me a few more questions. I gradually mastered the rules: the most simple and most effective method of composing 24 is multiplication. 24 can be 4 by 6, 3 by 8, 2 by 12. The algorithm consists of, if a card has any of these numbers, you can try to digitize the other three into its corresponding number, for example 1, 2, 3, 4. There are 3, then 1, 2, 4, to 8, can be listed as: 2 �� 1 �� 4 �� 3; if a group of cards do not have 3, 8 of these numbers, they can be resolved into 4,6; 2,12 These two combinations of numbers, for example: 2, 4, 6, 8 can be listed as (8��4)��(2��6)=2 can also use multiplication and other methods of addition Marlboro Lights, subtraction and division, such as the above 2, 4, 6, and 8, can also be listed as the following calculation method: (2 �� 6) + (4e, so I told my mother the rules of the operation that I mastered. My mother said it right, but she threw a question to me: "That 1 ��10 How many combinations can there be in these 10 digital cards?�� ��Wow, if 10 digital cards are taken four times at a time and they are not repeated, how many kinds do you have, wait until I finish, I don��t know how to count them. When is it!" I was discouraged at first, and even shook my head Marlboro Cigarettes Price, but after my mother's encouragement, I seriously counted it. If you want to count all of their combinations, you must first fix the first three numbers, the latter number will be arranged from small to large, and by 10, change the third number, so that you can calculate the result. I quickly calculated and found a very wonderful law. If I calculated according to my method, from small to large: if the second number is 2, then no matter what the number is in front, there are only 28 combinations in the back, if the number is 3, there are 21 kinds, there are numbers 4, there are 15 kinds... Do you find the law? The difference between 28 and 21 is 7, 21 and 15 are different. 6 In this case, there are 84 combinations at the beginning of the number 1, 56 combinations at the beginning of the number 2, and 35 at the beginning of the number 3. The number 4 starts with 20 combinations, there are 10 combinations at the beginning of the number 5, 4 combinations at the beginning of the number 6, and a combination of the numbers 7 at the beginning, after which the number 8, the number 9, the number 10 at the beginning are repeated in the previous combination. Then 1 to 10 of these 10 cards take 4 sheets at a time Cigarette Online, a total of 210 combinations.nfinity. I think, as long as we use our brains and think hard, then the key to open the door to wisdom will be in your hands.