Very interesting math problems, what are some interesting math problems?

The upstairs method doesn't work, once the last time is heavy on one side and light on the other, then how to tell which is the different ball?

Take 12 scales first, 6 on one side, and the balance is the ball you are looking for; Unbalanced divide the 6 balls at the heavy end into 3 balls on one side to weigh, and then weigh the 3 balls at the heavy end with 2 balls and 1 on each side, and the balance balance is the ball you are looking for, and the ball at the heavy end of the unbalanced side is the ball you are looking for.

A chicken that lays 5 eggs in 5 days. How many chickens do you need for 100 eggs in 100 days?

How many buckets of water do individuals use for 3 days and 9 people use for 9 days?

3.How long does it take for three children to eat three loaves of bread, and ninety for ninety children?

4.How do I use the simplest way to make the x+i=ix equation true?

5.It costs 214 yuan to buy a pair of high-end women's leather shoes and 5 jiao and 6 cents, how much does it cost to buy one?

6.There are three children guessing boxing, one out of scissors, one out of rock, one out of cloth, how many fingers do the three people have?

7.What would be the thing that wastes one-third of a person's life?

8.Can an 11 cm ruler be used to measure the length of any whole centimeter between 1 and 11 cm with only 3 integer scales? If so, which scales should be engraved?

9.In the exam, Xiaohua rolls the dice to determine the answer, but there are 20 questions, why did he throw it 40 times?

10.It takes 30 seconds for a wall clock to ring six times, and how many seconds does it take to strike 12 times?

11.When is 4-3=5?

12.Aunt Wang has three sons, and each of these three sons has an older sister and younger sister, how many children does Aunt Wang have?

13.There are six oranges in a plastic bag, how do you divide them equally among three children, and there are still two oranges in the plastic bag? (You can't separate the oranges).

The number "8", how do you make it equal to 1000?

15.When does four minus one equal five?

p(2，4)=2×3×4=24

p(3，5)=3×4×5=60

p(1，5)=1×2×3×4×5=120

p(4，6)=4×5×6=120

It is to multiply from the first number to the second number.

There was a guy who went to buy green onions.

Ask how much is a pound of green onions.

The person who sells green onions says, "1 yuan and 1 catty, this is 100 catties." After 100 yuan, the person who bought green onions asked again, "Do you sell green onions separately?"

The person who sells green onions says that the green onion is white 7 cents and the green onion is 3 cents.

The people who bought the green onions bought it.

Weigh 50 catties of green onion white and 50 catties of green onion.

The last calculation of green onion white 50 * 7 is equal to 35 yuan.

Green 50*3 is equal to 15 yuan.

35+15 equals 50 yuan.

The person who bought the green onion gave 50 yuan to the person who sold the green onion and left.

And the man who sold the green onion wondered.

Why do you want to sell green onions for 100 yuan?

And why did the person who bought the green onion buy it for 50 yuan?

What do you say it is.

If you think about it like this, since the waiter returned one yuan each, it means that the three people spent a total of 27 yuan, of which 25 yuan went to the boss and the other two yuan went to the waiter.

3*9=27 actually includes the two yuan of the waiter, 27 yuan makes them spend, plus the 3 yuan returned to them by the waiter, which is 30

It should be that since no one has come out of 25, there is no longer one person out of 8 yuan, so the back is not right.

）.There is a well 7 meters deep.

There was a snail climbing up from the bottom of the well.

Climb 3 meters during the day and drop 2 meters at night.

Q: How many days can a snail crawl out of a well?

zsxu

In the same high school, he didn't dare to go to her, although in the eyes of others, it couldn't be easier. Crush, is the only thing he can.

Things to do. He can only forget her position when he exercises between classes every day, and watch her favorite movements, which is enough. Lottery on the playground.

Bricks, your position is where they can stand, and their relationship is as fixed as brick to brick, and cannot be shaken.

I still remember the brick-laying workers who laid the whole playground into squares, that is, the last four pieces were turned into a square. Excuse me: the two of them.

The range of values for the slope of the line to which the position is connected.

The waiter hid it for 2 yuan.

Plus $3 returned.

In addition to $25.

$30 in total.

The $25 plus the total amount refunded is $30.

In order to save the face of their ancestors' failed race, the rabbit family in modern society decided to race with the turtle family again. In order to show their strength, the rabbit family said that they would let the turtle run 500 meters (2000 meters in the whole journey) first.

After the Kametomi family received the war letter, they held a clan meeting to discuss countermeasures. It is impossible for the turtle to win according to its strength, but it does not want to lose the face of its ancestors. Just then, a turtle appeared, claiming to outsmart its opponent.

In the end, the turtle family's reply: in modern society, physique is important, but intelligence is more important. We can beat you on the table, so why race, see you on the table!

The rabbit family thinks that strength determines everything, and they are not afraid to go to the table, so they readily agreed!

In front of the table, the turtle said: Because of your arrogance, you have lost the opportunity to save the face of your ancestors. Here's what I have to say.

Turtle Turtle Turtle Turtle Turtle Turtle

Rabbit Rabbit Rabbit Rabbit....

After the race starts, the turtle goes to A first, and the rabbit runs again. It takes time T1 for the rabbit to reach A, and it takes time for the turtle to run to B in time T1; It takes time t2 for the rabbit to run to B, and it takes time T2 to get to C; It takes time for the rabbit to run to C, and it takes time for the rabbit to run to C, and in T3 time, the turtle runs to D, and so on, and the rabbit can only get infinitely close to the turtle, but it can't catch up with the turtle, so the rabbit must not be able to win the tortoise.

The rabbit family thought for a long time and did not find a problem with the tortoise's reasoning. I regretted letting the turtle run 500 meters first, but I regretted that it was too late, so I could only admit defeat and go home.

But if we think about it, in reality, the rabbit can catch up with the turtle, but why is that? What is wrong with the turtle's reasoning?

Question: I watched a cross talk: a person buys bananas, and the seller says 1 yuan and 1 pound of bananas. The buyer said to buy 100 catties.

But he said he was going to peel it. The seller said that the banana has 50 catties of skin and 50 catties of meat. Buy this and give him 2 cents a pound of skin.

8 cents a pound of meat, how can it only be 50 yuan in the end. It should be 100.

The answer is that when bananas are sold for 1 yuan per catty, they are measured by weight, that is, each catty (skin or meat) is sold for 1 yuan, so 50 catties of skin should be 1 yuan and 1 catty, and 50 catties of meat should also be 1 yuan and 1 catty. The correct algorithm is:

Question: 3 people went to stay, each gave 10 yuan, and then the boss was merciful and wanted to return 5 yuan to each of them, but the waiter was super dark, and took 6 yuan as a tip, so the waiter returned 3 yuan per person, and each person paid 7 yuan 7 3 21 The waiter took 6 yuan, so they only paid a total of 27 yuan!! What about 3 more pieces??

Accommodation question (last question): 10 yuan per person, the waiter takes 6 yuan, that is, the average person gets 2 yuan, then each person pays 8 yuan, instead of 7 yuan, and they are given 3 yuan, and each person pays 5 yuan. So 5 3 = 15.

3 yuan per person will be refunded, which is 9 yuan, and the tip is 6 yuan, 9+6=. (Here's the point: After the tip is requested, each person pays 8 yuan, not 7 yuan.)

At least 118 points. If you want the third person to have the lowest score, you must have the first three people with the highest score, 160, 159, 158, and the first three combined scores are 72 higher than the average, and one of them is 98 and 37 below the averageWith 72-37 = 35 and then 35 2 = that is, these two people are 17,18 points lower than the average score.

Subtract 17 points from the average score to get a third person of 118 (if there are duplicate fractions or decimals, they can be calculated in this way).

60 corresponds to 2 copies, 60 divided by 2 equals 3030 times 7 = 210, A and B two warehouses originally 210 bags.

1) 56 in addition to the free state to 2 to get that put one-fifth of bag A flour into bag B, after the two belts have 28 kilograms, 28 divided by 4 5 to obtain the original flour of bag A 35 kilograms;

2) A = 800 B.

Third. 3) A originally had 120 bags, B originally had 90 bags;

4) The weight ratio of sugar to water after mixing sail mill is 9:4;

The Lord of the Hope Wheel can use it.

1. From the inscription, B is less than A: 2*1 5=2 5, then A is: 56 [1+3 5]=35 kg.

B is: 56-35 = 21 kg.

2, A is another relative Hu Wai three people 1 2

That is, divide the total into 3 parts.

A accounts for one-third of the total number of high-modulus barricades.

The remaining three accounted for two-thirds. The same thing.

B accounts for a quarter of the total.

C accounts for one-fifth of the total, and D accounts for it.

The total is 520 (13 60) = 2400 yuan.

It's good to ask for everyone's money.

A 2400 * 1 3 = 800 B. Third.

From Ze's Vanveda theorem: +

m/-4m)

So when m is not nuclear front equal to 0, -(m -4m).

Intentional Sun Hail.

So when m is not equal to 0, +1 4