Let's first learn the solution of two funny puzzles of mathematics. As I have asked, a couple's two sons and boys each have one sister. Then the total number of children in that couple? If the answer is not attentive then it will be wrong. It seems that if each one of the two sons has one sister, then two brothers, two siblings, all four siblings! No, then it will be wrong. Because, one sister became one of the two brothers when she was alone. So the number of siblings is three. So the couple's number of children is not four, three.
See another puzzle. Tell me, the sum of one pair and one odd number will be evenly or will it be odd? Answer: We know, odd ones. But the evidence is less? How to prove that oddity will always be there? For the proof of this, we will assume that if there are any natural numbers, few and sorrow, then the even number will be 2 and odd numbers (2 B + 1). These two numbers are added, (2 few) + (2 + 1) = 2 (few + sorrow) + 1. Now (few + sorrow) is a full normal number, it's even wider or odd-this is it. If you multiplied by 2, then surely the number of times. Adding 1 with it will definitely be odd. Therefore, the evidence is sure, that the sum of a pair and an odd number will always be odd. With the same logic, we can easily prove that the sum of the two pairs of pairs and the sum of two odd numbers are always the same number.
This week's puzzle
If the sum of a digit of three numbers is 12, and the number is less than the decimal of the house, the digit is less than 1, and the number of the unit's cell is less than 1, then what is the number?
Very simple. Find an instant solution. Send an email to a comment form or email [email protected]. For the right answer, see online Sunday.
Last week's puzzle answers
The puzzle was such: 3 the last digit (digit) of the 17 digit number?
Answer:
Last digit = 3
How did you answer?
We see, 3 1 = 3, 3 = 9, 3 3 = 27, 3 4 = 81, 3 5 = 243, 3 6 = 729, 3 7 = 2118, 3 8 = 6561, 39 = 19683 etc. Now, if I have 3, the power of 1, 2, 3, 4, then the last digit of their value is 3, 9, 7 and 1 respectively. If the value increases as the power grows, the last digit of every four numbers goes from 3, 9, 7 and 1, respectively. In other words, the last digit of every fourth consecutive value is repeated in the same sequence. So 3 means 17 means we divide 17 by 4 to find the last digit. Remaining 1 So if 3 is the power 1, then the last digit is the same. That is, the last digit is 3.
Now we can use the calculator to see it. 3 17 = 129140163. Last digit 3
The strategy here is that we have calculated the values of the first few numbers, and how many ratios it is that the last digit is repeated. I could easily find the answer.
The same technique can be used in other cases. For example, if we ask for the last digit of 23, then we will see that 2 is 1, 2, 3, 4, then every 4 times after the last digit is 2, 4, 8 and 6 respectively. Now it is left to divide 23 to 4. So the last digit of the 23rd will be 8. 2 23 = 8388608. Similarly, we can say that the last digit of 7 14 is 9. Because, 14 is divided by 4 divided by 4 Since 7 is equal to 2 = 49, so for 7 14, the last digit is 9. 714 = 678223072849.
In these three cases, the number of times the number of times received after every four power has been repeated. But this is not always the case. Have to check. Such as (4) 1 = 4, (4) 2 = 16, but (4) 3 = 64 and (4) 4 = 256. The last digit of the number obtained after two power has been repeated here. So, in this case, the accounts will be changed.