1, add the numbers in sequence.

In the following order, the next number should be?

2、5、 14、4 1

Answer: 122 (*3- 1)

2. Guess mathematical terms

1 .8 knives. 2. Car print. 3. look forward to each other. 4. Manual calculation. 5. midway. 6. Audit the accounts. 7. detour. 8. Bye, Mom.

9. Five cents. 10, almost. 1 1, member. 12, the number of moves. 13, no change. 14, lost contact.

15, move forward side by side. 16, see you at the usual place. 17, the doctor raised his pen. 18,54321.19, each as much.

20. Don't cheat in the exam.

answer

1. decomposition. 2. Trajectory. 3. Equality. 4. Index. 5. radius. 6.logarithm. 7. curve. 8. Denominator. 9. Half angle

10, similar. 1 1, the center of the circle. 12, operation. 13, integer. 14, line segment (broken). 15, parallel. 16, origin.

17, prescription. 18, countdown. 19, average. 20. Real score.

3. How old is this boy?

"How old is this boy?" Asked the conductor. Someone was deeply interested in his family affairs, which really flattered the country people. He proudly replied, "My son is five times as old as my daughter, my wife is five times as old as my son, and my wife is twice as old as my wife. If we add up all our ages, it happens to be my grandmother's age. Today she is about to celebrate the birthday of 8 1. "

How old is that boy?

answer

The age of the little boy is 5 years old.

4, 100 meter sprint answer

A and B sprint 100 meters. Results A reached the finish line 10 meter ahead of schedule. B and c compete 100 meter sprint. As a result, B won by 10 meter. Now that A and C are competing, how many meters will A lead?

Answer: If your answer is "A wins by 20 meters", it is wrong. The speed difference between A and B is 10%, and the speed difference between B and C is also 10%, but it cannot be concluded that the speed difference between A and C is 20%. As shown in the figure, if three people compete together, when A reaches the finish line, the distance behind A is 100 m 10%, that is, 10 m; The distance between C and B is 90 meters 10%, which is 9 meters. So if A and C compete, A leads 19 meters.

5. Who will win?

Two brothers took part in the 100 meter sprint. As a result, my brother won 3 meters. In other words, when my brother reached the finish line, my brother ran 97 meters. The two brothers decided to play again. This time, my brother retreated 3 meters from the starting line and began to run. Assuming that the speed of the two players is the same in the second game, who won the second game?

Answer:

Some people may think that the result of the second game is a draw, but this answer is wrong. Because from the first race, it can be seen that the time required for my brother to run 100 meters is the same as that for my brother to run 97 meters. So, as shown in the figure, in the second race, my younger brother and my younger brother reached the AB line at the same time. In the remaining 3 meters, because my younger brother is fast, of course, he reached the finish line first.

6. Colored socks

There are 10 red socks and 10 blue socks in the wardrobe drawer. These 20 socks are all the same except the color. Now the room is dark, and you want to take out two socks of the same color from the drawer. How many socks must be taken out of the drawer at least to ensure that the two colors are the same?

Answer: Many people who try to solve this interesting problem will say to themselves, "Suppose the first thing I take out is red socks. I need to take out another red sock to match, but the second sock I take out may be blue socks, the next one, the next one, and so on, all of which may be blue socks until all the 10 blue socks in the drawer are taken out. So, the next one must be the red socks. So the answer must be 12 socks. "

However, this reasoning ignores something. The topic is not limited to a pair of red socks, just take out two socks with the same color, so you can pair them. If the first two socks can't be paired, then the third one can definitely be paired with one of the first two socks. So the correct answer is three socks.

7. How do you divide the apples?

There are five students in Xiaomi's family Xiaomi's father wants to entertain these six friends with apples, but there are only five apples at home. What shall we do? I have to cut the apple, but it can be cut into pieces. Xiaomi's father wants each apple to be cut into three pieces at most. This has become another topic: divide five apples equally among six children, and each apple is not allowed to be cut into more than three pieces.

How did Xiaomi's father do it?

Answer: apples are divided like this: cut three apples in half and give six and a half apples each 1 block. The other two apples were each cut into three equal parts, and the six apples of 1/3 were also given to each person 1 piece. As a result, each child got half an apple and one 1/3 apple, and all six children were given apples equally.

8. Legacy issues

A widow will share her husband's 3500 yuan inheritance with her soon-to-be-born child. If a son is born, according to Roman law, the mother should get half of the son's share; If the child is a daughter, the mother should get twice the share of the daughter. But the fact is that twins-a man and a woman-were born.

How should the inheritance be distributed to meet the legal requirements?

Answer:

Widow deserves 65,438+0,000 yuan, son 2,000 yuan and daughter 500 yuan. In this way, the law is fully realized, because the widow's income is exactly half that of her son and twice that of her daughter.

9. The problem of two watches

I opened two watches at the same time, and later found that one watch was 2 minutes slow and the other watch was 1 minute fast. When I looked at my watch again, I found that the fast watch was faster than the slow watch 1 hour. How long has the watch been gone?

Answer:

One watch is 3 minutes faster than the other, so after 20 hours, their time difference is 1 hour.

10, egg price

"When I bought eggs, I paid the grocer 12 cents," said a chef, "but because they were too small, I asked him to add two eggs for me for free. In this way, the price per dozen (12 eggs) is lower than the original asking price 1 cent. " How many eggs did the cook buy?

Answer:

The chef bought 16 eggs at first, and the boss gave him two more, so the chef kept buying 18 eggs.

1