Do ten math problems
1. Use aluminum sheets to make canned beverage bottles. Each aluminum sheet can be used as 16 bottle bodies or 43 bottle bottoms, and one bottle body and two bottle bottoms can be used as a set. At present, there are 150 aluminum plates. How many bottles and bottoms can a complete set of beverage bottles use? Solution: set the X-ray as the bottom of the bottle. 43x * 2 = (150-x) *16x = 30, so 30 pieces are bottle bottoms. 2.A rides a bike from A to B at the speed of 12km, and B also rides a bike from B at the speed of 65430. The midpoint between B and AB is1.5km. Find the distance between AB and AB. Solution: Let it pass x hours,14x-1.5 =12xx = 0.7514 * 0.75-1.5 = 9 3. There are thousands of students in a school. 9-person team, 1 more. Similarly, each row of 8.7.6.5.4.3 or 2 people is 1 person. * * How many people are there? (Either way) The minimum common multiple of solution 2.3.4.5.6.7.8.9. 10 is 2520. 2520 plus 1 makes 2.3.4.5.6.7.8.9. 10 more than 1, so the answer is 252 1. A store will increase the original price of color TV by 40%, and then give a 20% discount. As a result, each color TV set earned more 270 yuan than the original price. What is the original price of each color TV? Let the original price x yuan X*( 1+0.4)*0.8=X+270 to solve the equation, and X=2250 yuan 5; The speed of the ship in still water is 14km/h, and the current speed is 2 km/h. The ship first leaves a wharf downstream and then returns against the current. If the ship is to return in 3 hours and 30 minutes, how far can the ship leave? Let x km x/(14+2)+x/(14-2) = 7/2, and x = 24 is obtained. 6. Patrol cars travel 200 kilometers every day, and each patrol car can be loaded with gasoline 14 days. At present, there are five patrol cars, starting from place A at the same time. In order to let the three of them patrol as much as possible (and then return together), after arriving at B, Party A and Party B only leave enough gasoline for themselves to return to the base, and the surplus gasoline is supplied to other cars. What is the longest driving distance of the other three cars? The solution is as follows: the key to the calculation of this problem is to determine the location of point B. Each car can travel 14 days with full fuel, and it can travel 200 kilometers every day, that is, it can travel 2800 kilometers. Point B should be the position where the remaining fuel after two cars leave to return fuel is exactly equal to the fuel consumption of three cars: 2800-b * 2 * 2 = b * 3, which means b = 800 kilometers. At this time, each car consumes 800 kilometers. The returned two cars each left 800 kilometers of oil return, and the remaining oil of the two cars was (2800-800-800) * 2 = 2400 kilometers. Divide into three parts, each 800 kilometers, just fill up the other three cars, so that the three cars can travel 2800+800 = 3600 kilometers. 7. A square. If one set of opposite sides is extended by 2cm first, and then the other set of opposite sides is reduced by 2cm, the rectangular area obtained at this time is exactly equal to the square area after the side length of the original square is reduced by 1cm, and the original square area is calculated. Let the length of the original square be x, then the length, width and area of the rectangle are x+2, x-2 and (x+2)*(x-2). The square area after the side length of the original square is reduced by one centimeter is (x- 1). The side length x obtained by the equation is 2.5 and the area is 6.25 8. The combined age of Party A and Party B is 50 this year. When Party A is 50 years old, Solution: Suppose Party A is X years old this year, then Party B is (50-x) years old this year. Equivalence relationship: age difference is constant (50-x)-x = (50-x)/2-(50-x) x = 30a: A is 30 years old and B is 20 years old. 2, a two-digit number, the ten-digit number is twice that of the single-digit number, and the two-digit number obtained after switching the two-digit number is 36 smaller than the original number. How to find these two numbers? Solution: Let the unit number be X 10(2X). +x-36 = 1x+2x20x+x-36 = 12x 2 1x-36 = 12x 2 1x- 12x = 369 x = 36x = 44x2x 65438。 The production of 500 machine tools, due to technical improvement, A factory exceeded the monthly production by 10%, and B factory exceeded the monthly production by 15%. As a result, the two factories produced 60 more machines. How many machines does factory B plan to produce every month? Solution: If Factory B plans to produce X units per month, then Factory A plans to produce (500-X) units per month. 15% x+10% (500-x) = 6015% x+50-10% x = 605% x =10x = 200 Test: 4. There are two shepherds. Each of them has x sheep. A said, B, if you give me a sheep, the number of my sheep will be twice that of yours. B said: or you give me one of your sheep, and our number will be the same. How many sheep are there in A and B? A: 7B: 5 5. One day, a boss sold two different calculators at the price of 38 yuan. One earned 20% and the other lost 20%. Ask the boss about his profit in this transaction? Solution: (1+20%)x=38, x = 312/3; (1-20%)y=38, y=47 and 1/2. So I earned 38-3 1 and 2/3=6 and 1/3, and lost 47 and 1/2-38=9 and 1/2, so I lost 9 and 1/2-6. Solution: Let the waist length be 2cm and the bottom length be Ycm. According to the meaningful equation, X+2X=9①, X+Y= 15② or x+2x =15 3x+y = 9 ④ It is not practical to solve the equation of ① ② and get X=3, Y= 12. If we solve the equations of ③ ④, we can get X = 5 and Y = 4. So the waist length of the triangle is 10cm, and the bottom length is 4cm. Remember to give me points if you give more ~ ~. %D%A