Answers to fun math questions for second grade

Answers to interesting math questions for second grade

Where did the one dollar go?

Little monkey, little bear,

Puppies met on the street Play on. When they came to the supermarket, they saw that a honeydew melon cost exactly 30 yuan, so each of them took 10 yuan and bought a melon. As soon as they walked out of the door, a salesperson ran out and said: "Today we have a special offer of only 25 yuan. This is the change of 5 yuan for you." The puppy said: "Let's share the 5 yuan!" The little bear said: " "Okay!" But the little monkey said, "We can't divide it all! Let's take 1 yuan per person and buy a bag of melon seeds for the remaining two yuan." Both the puppy and the bear agreed.

On the way back, Little Bear said: "We spent 9 yuan per person. For 3 people, 3 times 9 equals 27 yuan. We also bought a pack of melon seeds, which cost 29 yuan per pound. Where did the other dollar go?" The little monkey and the puppy said, "Yes! Why is there one dollar missing?"

Children, do you know where the dollar went? ?

It turns out that 27 yuan includes 2 yuan for buying melon seeds, plus one yuan for each person, the total is exactly 30 yuan, which is correct.

When did the snail climb up the well?

A snail accidentally fell into a dry well. It lay down at the bottom of the well and cried. A lai toad crawled over and said angrily to the snail: "Stop crying, little brother! It's useless to cry. The wall of this well is too high. If you fall here, you will have to live here. I'm already here It's been many years here, and I haven't seen the sun for a long time, let alone want to eat swan meat." The snail looked at the old and ugly toad and thought to himself: "The world outside the well is so beautiful, I will never be like it! Living like that at the bottom of a dark and cold well!" The snail said to the toad, "Uncle Legg, I must climb up!" "How deep is this well?" "Hahaha..." p>

What a joke! This well is 20 meters deep. How can you climb up at such a young age and with such a heavy shell on your back? "I am not afraid of hardship or fatigue. I can always climb a section every day." Climb out!" The next day, the snail was full of food and drank enough water, and began to climb up the well wall. It kept climbing, and finally climbed 3 meters in the evening. The snail was very happy and thought: "At this speed, I will be able to climb up tomorrow evening." Thinking about it, it fell asleep unknowingly. In the morning, the snail was awakened by a snoring sound. At first glance, it turned out that the leprous uncle was still sleeping. It was startled: "Why am I so close to the bottom of the well?" It turned out that the snail slipped down 2 meters from the well wall after falling asleep. The snail sighed, gritted his teeth and began to climb up again. In the evening, it climbed another 3 meters, but at night the snail slid down another 2 meters. Climbing and crawling, the snail finally climbed onto the well platform. Children, can you guess how many days it takes a snail to climb up the well platform? 18 days.

Digital Letter

There is a person who is very serious about his work and has good skills, but he has a shortcoming: he only gets drunk after drinking. When you get drunk, you either curse or get into fights. Relatives and friends all advised him to drink less or even stop drinking, but he could not change his behavior.

One day, this friend who loves drinking received a letter. When I opened it, I saw that the letters were all filled with numbers:

99 8179 7954 76229 8406 9405 769 18934 1.291817

Strange, what do so many numbers mean? Why is there no text description at all?

Is it a bill? Is it the account number and amount of the bank deposit slip? Is it a password? Is it a joke among friends, or is it a threat and blackmail from a bad guy? The more I think about it, the more nervous I become, and the more I think about it, the more afraid I become, so quickly find the right math teacher for help.

The math teacher read the letter carefully several times and asked: "Does your little nephew like to watch TV?"

"Why doesn't he like to watch it? He often imitates the speech on TV. , with a southern accent and a northern accent, he would call me uncle at one moment and ask me to move my waist at another.

"

"Want you to move your waist? ”

“Where, my nephew made me Sheriff No. 001! He said that the policeman on the TV was holding a walkie-talkie. If he wanted to find the person codenamed 01, he would shout "move, move the waist"; if he wanted to find 02, he would shout "move two, move two". When he saw me 001, he shouted "move your waist". "

The math teacher smiled slightly and said: "That's right. If you are afraid of mishearing the numbers on the phone, 0 is pronounced as "hole", 1 is pronounced as "unit", and 2 is pronounced as "两". This letter is written by your good nephew who speaks with a southern and northern accent. I'll read it out and you can listen to it. ”

This letter, which is full of numbers, turns out to be like this:

Uncle, don’t eat wine, eat wine, make mistakes, eat two ounces of wine, either get angry or use force, eat wine I'm going to be killed by wine

Don't eat any wine. After hearing this, my uncle blushed to the bottom of his ears and said repeatedly: "Don't eat it!" Don't eat! ”

Interesting question 1

1. There were originally 12 lit candles on the table. First, 3 candles were blown out by the wind, and soon another gust of wind blew out 2 candles. Finally, the table How many candles are left?

2. The fox bought a 45 yuan leather jacket from the old goat shop with a counterfeit 50 yuan bill. The old goat also gave the fox 5 yuan in change. So do you know how much money the old goat lost? 50

3. 24 people lined up in a row and reported numbers one and two. The person who reported number two took two steps forward and asked: Don't you stay where you are? How many people are moving? 12

4. There are 5 lights on one side of the alley, 8 meters apart. How long is this alley?

5. There are 10 cars in a line. Counting from front to back, the black car is the 6th car. So, counting from the back to the front, which car is it?

Interesting Question 2

1. Find patterns and write numbers

628, 629, 630, (631), (632) (633)

106, 108, 110, ( 112), (114), (116)

525, 530, 535, (540), (545), (550)

521, 531, 541, (551) , (561), (571)

192, 292, 392, (492), (592), (692)

2. Use the three numbers 1, 2, and 3 , how many different three-digit numbers can be written? 6

3. For a three-digit number, the number in the hundreds place is the largest one-digit number, and the number in the units place is the tens place. 2 times the number on, this number may be (912), (924), (936), (948)

4. A four-digit number, the number in the highest digit is 2, the hundreds digit The number in the highest digit is half of the number in the highest digit, the number in the tens digit is three times the number in the hundreds digit, the number in the ones digit is the same as the number in the hundreds digit, this number is (

2131).

5. A four-digit number, the first digit on the right is 3, the third digit is 2, the number in the tens place is 3 times the number in the hundreds place, these four The sum of the numbers is 13. What is this four-digit number? 2623

6. Xiaodong has 10 yuan and Xiaohua has 16 yuan. How many yuan does Xiaohua give to Xiaodong?

Both people have the same amount of money? 3 yuan

Interesting question 3

1. How many ends does a three-and-a-half rope have?

2. After giving 9 books to the first grade, the second grade has the same number of books. How many more books do the second grade have than the first grade?

3. Two. Engineering team *** has 100 people. If 20 people are transferred from team A to team B, the number of people in the two engineering teams will be the same. How many people do team A have? 70 people and team B 30. p>4. In the world of numbers, some numbers are often arranged according to certain rules. If we can observe carefully, analyze and think carefully, we will definitely discover the rules and solve the problems you face easily.

The following is an arrangement of related numbers. Can you find their patterns? Which row has a different pattern from the other three rows? Give it a try, and if you find the right one, I'll send you flowers. Never lose an opportunity. (3) Row

(1) 6, 7, 8, 9, 10

(2) 5, 6, 7, 8, 9

( 3) 2, 4, 6, 8, 10

(4) 3, 4, 5, 6, 7

Can you find the arrangement of these numbers? After finding it, fill in the appropriate number in the brackets.

(1)5, 10, 15, 20, 25, (30), (35), (40).

(2)1, 3, 5, 7, 9, 11, (13), (15), (17).

(3)3, 6, 9, 12, 15, 18, (21), (24), (27).

(4) 2, 4, 8, 16, 32 | (64) (128), (256).

(5) 64, 56, 48, 40, (32), (24), (16).

(6) 960, 480, 240, (120), (60); Interesting question 4; 1. Three people A, B and C stand in a row and take pictures. Are there (6) ways to arrange them?; 2. (1) (1) gt; (1) × (1) [in parentheses; 3. (2) (2) = (2) × (2) [must be added in parentheses; 4. (1) × ( 2) Easy to use

(6) 960, 480, 240, (120), (60), (30)

Interesting question 4

1.A. Three people, B and C, stand in a row and take pictures. Are there (6) ways to arrange them?

2. (1) (1) gt; (1) × (1) [The same words must be added in brackets? Integer]

3. (2) (2) = (2)×(2) [The same integer must be added in the brackets]

4. (1)×(2) × (3) = (1) (2) (3) 5. There were 10 candles in a house. A gust of wind blew out 6 candles. Mom closed the doors and windows in the house in the morning (

10) candles

6. Mom gave Xiao Ming a big box with 6 paper boxes in it, and each paper box contained 4 small boxes. Xiao Ming had (31). ) box.

7. There is a long-distance running competition on the sports field. There are 7 people running in front of each athlete, and there are also 7 people running behind each athlete. Now There are (15

) athletes on the sports field.