So please write the formula and process, 1. For a project, Party A and Party B work together for 4 days, and then Party B completes the project alone for 5 days. It is known that Party A completes 1% more than Party B every day? 2. It takes 19.8 hours to travel from city a to city B by train at the beginning of 1998. In 1998, the train speed was increased by 30% for the first time, 25% for the second time in 1999, and 20% for the third time in 2000. After these three increases, how many hours does it take to travel from city a to city B by train? 3. Car a can travel 20 kilometers per hour, car B can travel 30 kilometers per hour. After the two cars leave city a at the same time, how long is the distance between them at least 100 kilometers? How many hours at most? 4. There used to be two piles of coal in the boiler room of the school, weighing 24 tons in total. Now we add 4 tons to the small pile of coal and use 1 / 4 from the pile of coal. The weight of the two piles of coal is exactly the same. How many tons of the two piles of coal should we calculate?

So please write the formula and process, 1. For a project, Party A and Party B work together for 4 days, and then Party B completes the project alone for 5 days. It is known that Party A completes 1% more than Party B every day? 2. It takes 19.8 hours to travel from city a to city B by train at the beginning of 1998. In 1998, the train speed was increased by 30% for the first time, 25% for the second time in 1999, and 20% for the third time in 2000. After these three increases, how many hours does it take to travel from city a to city B by train? 3. Car a can travel 20 kilometers per hour, car B can travel 30 kilometers per hour. After the two cars leave city a at the same time, how long is the distance between them at least 100 kilometers? How many hours at most? 4. There used to be two piles of coal in the boiler room of the school, weighing 24 tons in total. Now we add 4 tons to the small pile of coal and use 1 / 4 from the pile of coal. The weight of the two piles of coal is exactly the same. How many tons of the two piles of coal should we calculate?

1. Suppose: Party B completes this project every day, then Party A completes x + 1 / 304 (x + X + 1 / 30) + 5x = 1 x = 1 / 15, then x + 1 / 30 = 1 / 10, Party A 1 / 10 = 10 (days) and Party B 1 / 15 = 15 (days). 2. Suppose: the distance between Party A and Party B is 1 (it is OK to set it as X, and it will be about in the end)