2. Two adjacent even numbers are multiplied by a certain number respectively, and the difference between the two products is 100. What is a number?
3. Among the numbers of 1 00 from 100 to 100, there are () pairs with divisor quotient of 2, in which the pair with the smallest dividend and divisor is (), and the pair with the largest dividend and divisor is () and what number?
4. 1 Fold the rope in half, then fold it in half, and then cut it in the middle. * * * is cut into many segments?
Mother said to Qin Xiao, "I'll give you 90 cents. You can buy stamps at the post office, as long as there are three kinds of stamps of 3 points, 4 points and 8 points, each with the same number. " How many stamps can Qin Xiao buy back at most?
6. Choose five numbers from the six numbers of 8, 9, 16, 19, 23 and 27, so that the sum of three numbers is twice that of the other two numbers. How should I choose?
7. The product of a number multiplied by 4 is 900 less than the product of a number multiplied by 40. What's this number?
8. The sum of number A and number B is greater than the sum of number A and number C by 3. What is the difference between number C and number B?
Group b:
9. Divide 100 by the sum of 12 numbers, so that each number has the number "3". How to divide it?
10. There are 9 balls in the pocket, and each ball is marked with a number, namely 1, 2, 3, 4, 5, 6, 7, 8 and 9. A, B, C and D each take two balls out of their pockets. The sum of the two balls taken by A is 10, the difference between the two balls taken by B is 1, the product of the two balls taken by C is 24, and the quotient of the two balls taken by D is 3. Excuse me, what number is marked on the ball left in the pocket?
1 1. There are 22 kinds of common forest animals in circus, 22 kinds of animals have 40 feet, and the animals with two feet are twice as many as those with four feet. How many kinds of two-legged animals are there? (note: snakes with no feet)
12. Everyone in the old five has some lollipops, and the big one is much smaller than the small one. The boss himself gives some to everyone, and whoever has how many pieces will be given how many pieces; Then the second child will give some of the existing blocks to everyone, and whoever has them now will try to give them to them. The third child, the fourth child and the fifth child will do the same. The last five people each have 32 pieces of sugar. Excuse me, how many sweets are there?
Group c:
13. The calf said to people, "Yesterday, I played chess with two chess masters. There are two chessboards in front of me. I play two games of chess by myself and compete with these two masters at the same time. Guess who wins and who loses? " "You must have lost both sets." People know that the calf has just learned to play chess and can't even remember to walk. "No .. for the first time, both sets were tied. The second time, I lost a set and won a set. No matter how many times I play, I will not lose two games at the same time. " "You brag."
Two chess masters came out to prove that Mavericks didn't brag, and we didn't give in to chess. It was he who adopted a clever way to play chess with us. What clever way did the calf use?
14. I'm going to buy things with 2 yuan money. As long as it doesn't exceed 2 yuan, no matter how much I buy, I can come up with the right amount, and I don't need a salesman to change it.
But I don't want to bring a lot of change. I just want to bring the least coins and bills. So, how many coins should I bring? How many notes should I take?
15. 1×2×3×…×48×49×50=? The number of 50 of 1 is multiplied by 50, and the product is a very large number. It is difficult to calculate with a pen. If you use an electronic computer to calculate, you can quickly figure out that this is a 65-bit number. This 65-bit number has many zeros at the end. Now, please do a clever calculation. How many zeros are there? (Note: not 10 zero)
Answer:
Group A:1.8; 2.50; 3.50 pairs, 2 and 1, 100 and 50; Paragraph 4.5; 5.90 ÷ (3+4+8) = 6,6× 3 =18 sheets; 6. (8+19+23) ÷ (9+16) = 2 (times); 7.900÷(40-4)=25; 8. the number b is 3 larger than the number C.
Group B: 9.100 = 30+30+13+3+3+3+3+3+3; 10.7; 1 1. For example, the number of feet of biped is the same as that of quadruped, 40÷2=20 (one foot) and 20×2= 19 (one foot); 12. Analysis by reduction method, 80,41,2 1,1,6 blocks.
Group c: 13. For the convenience of explanation, we might as well give the two players two names: one is Gao Ming and the other is Bi Sheng. Mavericks and Gao Ming play chess, let Gao Ming go first; Another game of chess made Bi Sheng leave. Then the Mavericks look at the clever way and copy it to Bi Sheng, and then see which step Bi Sheng takes to move back to Gaoming. So, on the surface, the Mavericks play two games at the same time, but in fact, they are smart Bi Sheng. Gao Ming and Bi Sheng can't win at the same time, so the Mavericks won't lose both sets. 14. Coins: 1, 1, 2,5,1* * 4; Paper money: 65438+2 pieces of 0 cents, 1 piece of 2 cents, 1 piece of 5 cents, 65438+ 1 piece of 0 yuan * * 5 pieces. Of the fifty numbers from 15. 1 to 50, five have zeros at the end: 10, 20, 30, 40, 50, and the product of multiplication has six zeros at the end; There are five numbers with 5 at the end: 5, 15, 25, 35, 45. These five numbers are multiplied by even numbers without 0 at the end, and the product has six zeros at the end. Therefore, there are 12 zeros at the end of this 65-digit number. (Note: 50=5× 10, 25=5×5)