Brainstorming, in a country where boys are preferred to girls, every family wants to have a boy. If their child is a girl, they will have another child until it is a boy. What is the ratio of men to women in such a country? What is the answer? Playing such games with children at ordinary times can make children's brains turn fast, which plays an important role in cultivating children's divergent thinking, improving imagination, developing intelligence and expanding knowledge. Let me reveal the answer for you. I hope you like it.

Brainstorm: In a country where boys are preferred to girls, every family wants to have a boy. If their baby is a girl, they will have another baby until it is a boy. What is the ratio of men to women in such a country?

Answer: Because the probability of each child being born is 50%, the ratio of male to female is the same every time. Suppose there are n couples in this country, then n couples will have n boys, and that's what happens when they are born. Assuming that the probability of giving birth to boys and girls is 50%, then the first child gives birth to n/2 boys, and at the same time, there are n/2 couples who give birth to girls, among which n/4 couples give birth to boys and n/4 couples give birth to girls. N/8 couples give birth to girls, and so on, this country will give birth to n/2+n/4+n/8+ ... girls, so the male-female ratio is N: N/2+N/4+N/8+... = N: N =1:1.

Interesting brain teaser 1. Taste before buying a word-Answer: Sharp.

2. Who will the bystanders help when soy sauce and vinegar fight? Answer: They will help vinegar, because they all come to make soy sauce.

No one can beat Lu Xun's article-Answer: Kong Yiji.

4. Remarriage and playing movies with three-character classics-Answer: Rebirth

5. There is a horizontal character above and below twenty-A: Ping.

6. Willing to fight on an empty stomach-Answer: 20

7. Ten more words-answer: Yes.

8. A heifer looks like a button. Don't look weak and walk with your house on your back. Hit an animal-answer: snail

9. Ha ha Jing plays an idiom-A: They set each other off and become interesting.

10. Shanghainese type a word-answer: Shen.

1 1. Two people type a word to shareholders-answer: service.

12. Like a monkey with a tailless black tower, it is the smartest animal and good at juggling. Beating animals-answer: chimpanzees

13. Born, thin and long; Born, smart; Jumping down is very noisy; Fly, silently. Hit a natural object-answer: rain

14. Short and fat, with an empty stomach and a mirror in the middle; Meet two or three times a day and bow every time you meet. Hit a living creature-a: washbasin

15. Wolong in winter, canopy in summer, beard growing upwards and pearls growing downwards. Hit a fruit-answer: grapes

16. An idiom was typed in a 60-minute individual walk-answer: one step at a time.

17. The tree sees it waving, the flower sees it nodding, the seedling sees it bending, and the cloud sees it giving way. Hit a natural object-answer: wind

18. Xiaoming eats instant noodles at midnight. Why does he stare at his watch while eating? Answer: that bag of instant noodles is about to expire.

19. Go straight to the point and don't exaggerate. Type a word-answer: pollution

20. The white dog is getting fatter and fatter on the kang. Act a scene-A: Act cotton.

Classic brain teaser 1. Chinese name for heating fee-answer: farfarfara.

It is like rotten wood in the water, with a pair of small eyes and a long tail, and people and animals are afraid of it hiding. Hit an animal-answer: crocodile

3. The outlaw hero played an idiom-A: Every grass and tree is a soldier.

4. Don't wash your hands before eating? Answer: Popsicle.

5. Who is the most attractive, hands or feet? -Answer: Hands

6. Thirty days of suffering after typing a word-A: Hu

7. Look like a ruler horizontally and a stick vertically. He is the youngest, he will be the eldest brother. Dial a number-Answer: 1

8. Lao Wang shaves many times a day and still has a beard on his face. Why? Answer: He is shaving others.

9. A big bird is really strange. It can run fast without wings. When it is in danger, it will hide its head and stay outside the sand. Beating animals-answer: ostrich

10. The front legs are short and the rear legs are big, supported by a long tail, and the child is put in the pocket. The Australian grassland is his home. Hit an animal-answer: kangaroo

1 1. Give some love and make a good start-A: Ann.

12. throw the rice into the air and type a word-answer: O.

13. It is said that birds have faces like cats, but cats fly high. They sleep during the day and are busy at night. It is an honor to catch voles. Hit an animal-answer: owl

14. Plastic surgery is an idiom-answer: makeover.

15. Born without parents, they are called dolls, which are specially for children to play with and children like them. Hit a thing-answer: doll

16. Why did Mr. Chen say that he couldn't live a day without a woman? Answer: He is a cosmetics manufacturer.

17. Xiao Wang said that when the sun and the moon are together forever, he will travel. Is this possible? Answer: Maybe.

18. Xiao Wang went out in an empty taxi. Why didn't anyone wave him for a ride along the way? Answer: He took the highway.

19. Type a word at the big party and guess again-answer: prison.

20. My mother-in-law tattooed an educational term-Answer: Endorsement.