(1) Team A and Team B completed a project together. Team A needs 2/3 as many days as team B, because teams A and B can complete half of the project in 6 days. How many days does it take for Team A and Team B to complete all the projects by themselves? (2) Party A and Party B each walk 14km, Party A walks half an hour less than Party B, and the speed ratio of Party A and Party B is 8: 7. What is their speed? (3) The efficiency of typist A is 25% higher than that of typist B, and the time for typist A to type 2000 words is 5 minutes less than that for typist B to type 1800 words. How many words can typists A and B type per hour? (4) After the factory produced a product 15 pieces, the method was improved. The number of products produced per hour is equal to the original 1.5 times. Now the time to produce 20 pieces is 20 minutes less than that to produce 15 pieces. How many pieces are produced per hour? (5) The owner of a clothing store bought a number of shirts with 8,000 yuan, and sold them at the price of each 58 yuan, which was soon sold out. I also bought the same shirt for 17600 yuan, which was twice as much as the first time. The purchase price of each work exceeded the first time. It's 4 yuan, and the clothing store still sells it at 58 yuan. It's all sold out. What is the profit? (6) The distance between A and B is 160km. Two hours after a bus leaves from A, one or two cars leave from A with a speed ratio of 3: 1, and the bus arrives at B 40 minutes earlier than the bus. Find the speed of two cars. (7) A company completed the renovation project of the new office building within one month (365,438+0 days). If both parties cooperate on the two projects, it can be completed in 12 days. If two teams do it alone, Team A spends less than Team B10 ... ① Ask Party A and Party B how many days it takes to complete the project independently; (2) If Party A is invited to construct, the company will pay 2,000 yuan per day; If Party B is invited to construct, the company will pay 1400 yuan every day. Which of the above schemes costs the least within the specified time? (8) Prepare a new paint with a value of 100 yuan and a value of 240 yuan. Its price per kilogram is less than that of a 3 yuan coating and more than that of a coating 1 yuan. How much is this new coating per kilogram? (9) A shop assistant bought a batch of shirts with 80,000 yuan, all of which were sold, and bought a second batch of similar shirts with176,000 yuan, which was twice as much as the first batch, but the unit price was expensive in 4 yuan. Every shirt sold in the mall is priced in 58 yuan, and the last 150 shirt is 20% off. How much profit did you make? Reference answer:1) Team A and Team B * * * complete a project together, and the number of days it takes for Team A to complete it alone is 2/3 of that of Team B. Knowing that Team A and Team B can complete half of the project in six days, how many days does it take for Team A and Team B to complete all the projects alone? Solutions; Suppose it takes X days for B to complete it alone, then it takes 2X/3 days for A to complete it alone. 1/x+ 1/(2x/3)= 1/ 12 1/x+3/2x = 1/ 12+65438。 (2) Party A and Party B each walk 14km, Party A walks half an hour less than Party B, and the speed ratio of Party A and Party B is 8: 7. What is their speed? Solutions; Let the speed of A be 8X, then the speed of B is 7X, which is given by the following question:14/7x-14/8x =1214 * 8-14 * 7 = 28x28x = 7x = 7 *( 1/2)= 3.5km/h； The speed of A is 4 km/h, and the speed of B is 3. 5 kilometers per hour. (3) The efficiency of typist A is 25% higher than that of typist B, and the time for typist A to type 2000 words is 5 minutes less than that for typist B to type 1800 words. How many words can typists A and B type per hour? Solutions; Let A type X every hour and B type X-25% every hour. X = X-X/4 = 3x/4, right; 60[ 1800/(3x/4)]-60(2000/x)= 560[7200/3x-2000/x]= 560(7200-6000)= 15xx = 4 * 65433。 (4) After the factory produced a product 15 pieces, the method was improved. The number of products produced per hour is equal to the original 1.5 times. Now the time to produce 20 pieces is 20 minutes less than that to produce 15 pieces. How many pieces are produced per hour? Solutions; If X pieces were originally produced in the first hour, now 1.5X=3X/2 pieces are produced every hour. 60[ 15/x-20/(3x/2)]= 203( 15/x-40/3x)= 19 * 15- 120 = 3x3x = 65438。 I bought the same shirt at 17600, which was twice as expensive as the first time, and each one was more expensive than the first time. It's 4 yuan, and the clothing store still sells it at 58 yuan. It's all sold out. What's the profit? Solutions; If x pieces are purchased for the first time, the cost price is; 8000/X, the second purchase of 2X pieces, the cost price is 16700/2X, so the profit is; X (58-8000/x)+2x (58-17600/2x), from the title: 8000/x+4 =17600/2x16000+8x+/kloc-0. (6) The distance between A and B is 160km. Two hours after a bus leaves from A, one or two cars leave from A with a speed ratio of 3: 1, and the bus arrives at B 40 minutes earlier than the bus. Find the speed of two cars. Solutions; If the speed of the bus is X km/h and the speed of the car is 3xkm/h, yes; 60( 160/3X)+40 = 60( 160-2X)/X60 * 160+ 120 x = 180( 160-2X)60 * 160+ 120 x = 180 * 160-360x4 ... (7) A company completed the renovation project of the new office building within one month (365,438+0 days). If both parties cooperate on the two projects, it can be completed in 12 days. If two teams do it alone, Team A spends less than Team B10 ... ① Ask Party A and Party B how many days it takes to complete the project independently; (2) If Party A is invited to construct, the company will pay 2,000 yuan per day; If Party B is invited to construct, the company will pay 1400 yuan every day. Which of the above schemes costs the least within the specified time? Solutions; One; It takes X days for Party A to complete it alone, and X+ 10 days for Party B to complete it alone. Yes; 1/X+ 1/(X+ 10)= 1/ 12 12(X+ 10)+ 12x = X(X+ 10) 12x+ 120+ 12x = X 2+6552。 That is, it takes 20 days for A to do it alone and 30 days for B to do it alone. The cost of one-time completion is: 2000 * 20 = 40,000 yuan, and Party B will complete the cost alone; 1400 * 30 = 42,000 yuan. The cost of cooperation between Party A and Party B is: (2000+1400) *12 = 40,800 yuan. 4000 & lt40800 & lt4.2 42000, so it is most cost-effective to ask Party A to complete the construction alone. Spend the least. (8) Prepare a new paint with a value of 100 yuan and a value of 240 yuan. Its price per kilogram is less than that of a 3 yuan coating and more than that of a coating 1 yuan. How much is this new coating per kilogram? Solutions; Set a new paint at X yuan per kilogram, the price of paint A is X+3 yuan and the price of paint B is X; X- 1 yuan, yes; X [100/(x+3)+240/(x-1)] = 340x (x-1)100+240x (x+3) = 340 (x) (9) A shop assistant bought a batch of shirts with 80,000 yuan, all of which were sold, and bought a second batch of similar shirts with176,000 yuan, which was twice as much as the first batch, but the unit price was expensive in 4 yuan. Every shirt sold in the mall is priced in 58 yuan, and the last 150 shirt is 20% off. How much profit did you make? Solutions; The result of the fifth question above is: if there is no discount, the profit is 9200 yuan, then the discounted profit is 9200-58 * 20% *150 = 9200-58 *150/5 = 9200-58 * 30 = 9200-/. That is * * * profit of 7460 yuan. When the numerator =0, the value of this fraction is 0; When the denominator =0, the score is meaningless.