Mathematics application problem (small rise early help (1) When the fox runs 5 steps, the dog runs 3 steps. When the dog runs 4 steps, the fox runs 7 steps. Now that the fox has run 30 meters, the dog begins to chase it. How many meters can the dog chase the fox? (2) When the tax collection hall goes to work, the tax payers have already lined up for a long time, and the number of people is increasing at an even speed. If the hall has only five windows to work, it will take 10 hours to complete, and 12 windows to work at the same time, and it can be completed in three hours. Now, if you want to finish it in two hours, how many windows should you open at the same time?

Mathematics application problem (small rise early help (1) When the fox runs 5 steps, the dog runs 3 steps. When the dog runs 4 steps, the fox runs 7 steps. Now that the fox has run 30 meters, the dog begins to chase it. How many meters can the dog chase the fox? (2) When the tax collection hall goes to work, the tax payers have already lined up for a long time, and the number of people is increasing at an even speed. If the hall has only five windows to work, it will take 10 hours to complete, and 12 windows to work at the same time, and it can be completed in three hours. Now, if you want to finish it in two hours, how many windows should you open at the same time?

(1) You need to know the distance or time of a fox or dog
(2) Tax window office speed is 1
The number of people per hour increased evenly: (5 * 10-12 * 3) / (10-3) = 2
Number of people before tax window: 10 * (5-2) = 30 or 3 * (12-2) = 30
After 2 hours, the number of windows to be opened at the same time: 30 / 2 + 2 = 17