26. A, B and C are all 64 years old now. When A is 2 1 year, B is 17, and A is 18, C is three times as old as D. How old is D now?
27. There are three people in a family. My father is three years older than my mother. Now their ages add up to 80. 10 years ago, the total age of the whole family was 5 1 year. So, how old is my daughter this year?
Class 1, Grade 4 went boating. They rented some boats. If there are four people in each boat, there will be six more. If there are five people on each boat, there will be four empty seats. How many students and how many boats are there? 3 1. A workshop needs to complete a batch of parts. If each group completes 16 pieces, it will exceed 9 pieces. If each group completes 15 pieces, it will exceed 2 pieces. How many teams are there in this workshop? How many parts are there in this batch?
32. The whole class is arranged in several rows. If there are 14 people in each row, there will be 6 people missing. If there are 17 people in each row, there will be less 15 people. How many rows are there in this class? 33. The distance between A and B is 600 kilometers. At 8 o'clock in the morning, the bus travels from A to B, with an average speed of 60 kilometers per hour. The truck travels from B to A at an average speed of 50 kilometers per hour. What time must the truck leave in the morning so that the two cars meet at the midpoint of the journey?
35. Fill in the nine numbers 1-9 to form an equation, and each number can only be used once. □□□×□□=□□×□□=5568
The average score of these six children in the math exam is 92.5. Their scores are different integers, with the highest score of 99 and the lowest score of 76. Then, according to the score from high to low, how many points does the third-ranked classmate get at least? 39. The product of remainders 70352 and 63285 is divided by 7. What is the remainder?
On Children's Day, Xiao Xin's family went to the movies together. Tickets are 4 yuan for adults and 2 yuan for children. It took 14 yuan to buy a ticket. How many adults and children are there in Xiao Xin's family?
What is the product of 42.728×37×27× 125? (Simplified calculation)
45. Two hours after Xiao Ming came out from his grandfather's house, his father came out from his home 24 kilometers away to meet Xiao Ming. After 2.25 hours, if Xiao Ming came back from his grandfather's house two hours later and picked him up again, 1.75 hours later, what was the speed of Xiao Ming and his father?
46. Xiao Qiang and Liang Xiao discussed that they would leave home at 8 o'clock on Thursday morning. Think about it. Xiao Qiang walks 48 meters per minute, and Liang Xiao walks 54 meters per minute. They met at the midpoint of 30 meters. How long is the road between their two families? In the video game "Defending Home", two guards patrol the 20-meter-long road in front of Lele's house every day. The big guard walks 0.5 meters per second and the small guard walks 0.3 meters per second. Every morning, two people walk to each other from both ends of the two roads at the same time, go to the starting point of each other and then go back. How many meters did the guard walk when they met for the second time?
49. Two cars, A and B, set off from AB at the same time, heading in opposite directions, and meet at a distance of 42km. After meeting, they continue to drive to BA, immediately return at the original speed, and meet at a distance of 30km. How long is the road between AB?
52. Party A, Party B and Party C are all college students. Party A walks 50 meters per minute, Party B walks 60 meters per minute and Party C walks 70 meters per minute. One day, A and B went to the classroom from the dormitory, just as C returned to the dormitory from the classroom, and C met A after 1 minute. How long is the road between the classroom and the dormitory?
Every Sunday, Xiaoming and his parents go to see his grandfather. He walked 60 meters per minute when he went there and 40 meters per minute when he came back. What is their average speed back and forth?
Xiao Ming was sitting on the bus and saw his sister walking in the opposite direction. After 90 seconds, Xiao Ming got off and chased her. If his speed is 1 times faster than his sister's and the speed of the bus is five times that of Xiaoming's walking, how long will it take Xiaoming to catch up with her sister?
Master Zhang was hiking on the highway when a bus came. He asked the bus driver, "Is there a cyclist behind you?" The driver said, "I overtook a bike 20 minutes ago." Master Zhang calculated that if the speed of a bicycle is four times that of a human, you will meet a cyclist after another 30 minutes' walk. How many times has Master Zhang assumed that the speed of the car is the speed of his walking?
56. Beibei, a Jingba dog, races with baby Persian cat. Beibei's distance of 3 steps is equal to the baby's distance of 5 steps. Beibei runs 4 steps, the baby runs 7 steps and the baby runs 1470 steps to the finish line. How many steps does Beibei need to run to reach the finish line?