1, the classroom key is lost. Three children, Xiaoxiao, Naughty and Qingqing, each said a word: Xiaoxiao said: I didn't lie. Naughty said: Xiaoxiao is lying. Qing Qing said: Naughty and smiling are deceptive. Clever children, do you know which one of them must be lying? This year, our Yucai Group has four new young teachers, and our Yucai Group has four primary schools. We will arrange 1 teacher for each primary school. Three related teachers suggested this arrangement: Miss Li: C goes to Yucai Primary School and B goes to Yucai Primary School. Miss Wang: C goes to the second primary school and D to the third primary school. Teacher Zhang: A goes to the second primary school and D to the fourth primary school. The principal of the general school finally absorbed half of the suggestions of the relevant teachers. Do you know how the headmaster divided them? There are 32 football teams participating in the World Cup. They were divided into eight groups, and the first group match was held. Every two teams in the group will play a game. Do you know how many World Cup group matches have been played? 4. Fold a 12m long rope into three equal lengths, then fold it in half, and then cut it from the middle, then a * * * will be cut into () ropes, and the shortest one is () meters. The master chased his dog. The dog runs three steps and the owner runs two, but the dog needs to run two steps away from the owner. After the dog ran out of 10 step, the owner began to chase. When the owner caught up with the dog, the dog ran out (). 6. If the fish tail weighs 4 kilograms, the weight of the fish head is equal to the weight of the fish tail plus half the weight of the fish body, and the weight of the fish body is equal to the weight of the fish head plus the fish tail. This fish weighs 20 kilograms. 7. The sum of the ages of Xiaohong and Xiaolin is younger than that of Dad this year 16 years old. How old are they four years later? 8. 100 cups are packed in a box, the quantity of each box is different, the box is not empty, and at least () cups are needed. 9. Fill in a minimum natural number so that the last four digits of the product of 225×525× are all 0. 10, the postal code of a place can be expressed by ABCCDD. It is known that the sum of these six numbers is 8, the sum of A and B is equal to 2 D, and A is the smallest natural number. This postal code is (). Four football teams, A, B, C and D, 1 1, played round robin matches. After several games, I learned about the matches of Team A, Team B and Team C, but I didn't know the results of Team D. I ranked the known results as follows: winning and losing goals and conceding goals A 3 2 0 2 0 B 2 1 0 4 3 C 2 0 2 3 6 D Do you know the scores of the four teams? 12, the school arranges four classes of mathematics, Chinese, foreign languages and physical education in one morning. Mathematics can only be ranked in the first and second paragraphs, Chinese can only be ranked in the second and third paragraphs, and foreign languages must be ranked ahead of physical education. How should the class schedule be arranged? How many arrangements are there? 13, animal kingdom war, chickens and cats form a joint camp to kill pests! Two scouts sent by the pest came back to report, and the locust said, "There are too many. I count to 500! " The mouse said, "I almost died. I can't see my head." I only counted that they have 1200 legs! " "Can you count the number of cats and chickens in the chicken and cat camp? 14. Mother squirrel picks pine nuts. You can pick 20 pine nuts every day in sunny days and 12 in rainy days. It has continuously picked 1 12 pine nuts, averaging 14 pine nuts per day. How many rainy days are there these days? 15. Now we have a balance, a 500g and a 900g weight. How can I divide 2000 grams of salt into 10 equal parts and only weigh it 9 times? 16, A, B and C participated in the high jump, long jump and rope skipping competitions. According to the following conditions, judge which projects they participate in. (1) A didn't take part in the high jump; (2) B did not participate in the skipping competition; (3) Everyone participates in two activities; (4) There are two in each competition. 17, Xiao Lu, Lu Xiao and Xiao Zhao. One of them won the prize in the math contest. When the teacher asked them who was the winner, Xiao Lu said it was Xiao Lu, Xiao Lu said it wasn't me, and Xiao Zhao said it wasn't me. If only one of them tells the truth, who will win? 18, five students, A, B, C, D and Xiao Ming, play chess together, and each of them wants the next game. Up to now, A has played four sets, B three sets, C two sets and D 1 set. How many sets did Xiao Ming play? 19, a barber made a shop rule for himself: only shave all the people in the village who don't shave themselves. Excuse me: Should this barber shave himself? There are 100 trees on both sides of the road, and the distance between each tree is about 3 meters. A student started from the first tree and walked along the roadside to the last tree. Excuse me, how many meters did the student walk? When Qiang Qiang was 8 years old, his father was 32 years old. How old was his father when he was twice as old as Qiang Qiang? 22. There is a four-digit number. One digit is less than the hundredth 1, which is three times that of the tenth and half that of the hundredth. In addition, this four-digit number is known to be between 3000 and 4000. Do you know what this four-digit number is? 23. There are some sweets in the box. Xiao Ming took out half of it and put it back one candy at a time, so * * * operated it five times, and there were still three sweets in the box. Q: How many sweets are there in the box? 24. Tortoise and Rabbit Race. They set out at the same time, with a total distance of 7000 meters. The tortoise crawls at a speed of 30 meters per minute, and the rabbit runs at a speed of 330 meters per minute. After running for 10 minutes, the rabbit stopped to sleep for 200 minutes. When he woke up, he found that the tortoise had passed it and immediately chased it forward at the original speed. How many meters is it from the finish line when the rabbit catches up with the tortoise? 25. When a number is expanded by 10 times, the number obtained is 702 more than the original number. What is the original number? 26. There is a basket of apples. Take out more than half for the first time, and take out less than two remaining half for the second time. How many apples are left in the basket? 27. The rabbit is in front of the dog150m, jumping 2m at a time, and the dog is faster, jumping 3m at a time. How many steps does the dog need to jump to catch up with the rabbit? 28. The two groups have equal numbers of people and receive the same amount of jelly. The leader of group A distributed jelly: he divided himself into six parts, four parts for other team members, and the remaining eight parts; The group leader of group B distributes jelly: the group leader is divided into four parts, and the other members are divided into five parts. As a result, there were not enough jellies, but two were missing. How much jelly did these two groups receive? 29. Children share candy. If each person divides 8 capsules, there are still 18 capsules left. If the children of 10 get 7 pills each, and the rest of the children get 10 pills, it's over. How many children are there? How many sweets? 30. On the fourth grade Arbor Day, two classes should plant 102 saplings. Class one and class two are scrambling for seeds. Class 2 saw that 1 class picked too many seedlings, so it robbed the 10 tree. 1 class refused and got back six trees from class 2. At this time, the number of trees in 1 class is twice that in Class 2. How many trees did you take in the first class? 3 1, there are 26 cards, and Party A and Party B compete for it. When Party A saw that Party B had too many cards, he grabbed half of them. If Party B refuses to accept it, it will take half from Party A, and if Party B refuses to accept it, it will give five more cards. At this time, Party A takes two more cards than Party B. How many cards is Party B going to take at first? 32. When doing integer addition, Xiao Qiang regarded 6 in the unit as 9 and 8 in one tenth as 3, and the result was 123. What should be the correct answer? 33. There are red, white and black cards *** 158, which are arranged in the order of five red cards, four white cards and four black cards. What color is the last card and 140 card? 34, with a 38 cm long wire around the rectangle, so that their length and width are the whole cm, you can have () kinds of enclosing methods. 35. My grandfather is 75 years old, and the ages of his three grandchildren are 17, 15 and 13 respectively. How many years later, will the three grandchildren be the same age as my grandfather? 36. Wang Xue read a story book. On the first day, he read eight pages. After that, he read three more pages than the day before. On the last day, he read 32 pages and just finished reading them. How many days did she study? 37. The school bought some badminton and distributed it to all classes in the school. If every class has 16, it's just over; Give two classes less, each class gets 1, and the remaining 10. How many badminton players are there in the class? There are 78 kinds of chrysanthemums, roses and tulips in the flower shop, of which chrysanthemums are twice as many as roses and roses are three times as many as tulips. How many flowers are there in each of these three kinds of flowers? 39. To transport 58 tons of goods from City A to City B, if it is transported by a large truck with a load of 5 tons, the freight rate is 150 yuan; Shipment by medium-sized truck with a load of 2 tons, freight 80 yuan; Shipment by van, load 1 ton, freight 50 yuan. How many trucks, medium trucks and small trucks do you need to ship the goods at once with the least money? (Fill in numbers only, don't write formulas) Large trucks (), medium trucks () Small trucks () 40, dividend is 3320, quotient is 150, remainder is 20, and divisor is (). 4 1 and 3998 are the sum of four consecutive natural numbers, of which the smallest number is (). 42. Fill in the seven numbers "1-7" in the following equation respectively, (Numbers cannot be filled in repeatedly) () ×)=()⊙()=()+()-()43. There are three people wandering on an isolated island. They built a boat, but it can only carry 90 kilograms at most. 60 Jin. Ask them how to return to land safely by boat. 44,1994+1960+1976+1992+2008+2024+2040 = () .45. Choose from the nine numbers of 1-9. 46、A ÷ A ×( A + A )-( A × A + A - A )=？ 47. Party A, Party B and Party C shall have 750 yuan. If Party B borrows 30 yuan from Party A and then lends it to Party C's 50 yuan, as a result, three people hold equal RMB, one original () yuan and one original (