The project team originally planned to build 72 meters a day, but actually built 80 meters more every day, three days ahead of schedule. How many kilometers is the total length of the road Remember, the question is kilometer, 80 meters to unit Write arithmetic

72 × 3 = 216 (m)
216 △ 80 = 2.7 (days)
2.7 × (72 + 80) = 410.4 (m)
410.4m = 0.4104km

The project team planned to build a highway, which was originally planned to build 720 meters per day, but actually 80 meters more than the original plan per day. Therefore, the task was completed three days ahead of schedule. How many meters is the total length
Why do you do this!
Try not to use equations and explain why

Plan X days
720*x=（720+80）*（x-3）
x=30
Total meters = 720 * 30 = 21600

If you build a road 100 meters a day, it can be completed three days ahead of schedule. If you build 80 meters a day, it will be two days behind schedule. How long is the road
How to solve the equation without unknowns?

This problem is a typical profit and loss problem. First calculate the profit and loss difference of 100 × 3 + 80 × 2 = 460 meters, and then divide it by the difference of 100-80 = 20 (meters) every day to get the planned days of 23 days. Then choose one of the assumptions to calculate the total length of the road: 100 × (23-3) = 2000 (meters) or 80 × (23 + 2) = 2000 (...)

The correspondent originally planned to travel from place a to place B in 4 hours. Because of the urgent task, he accelerated by 2 km per hour. As a result, he arrived at place B 0.5 hours earlier
The journey of

If the time difference ratio is 0.5/4, then the speed difference ratio is 2 / (0.5 / 4) = 16, which is the original speed. 16 * 4 = 64 is the distance

The project team originally planned to build 72 meters a day, but actually built 80 meters more every day, three days ahead of schedule. How many kilometers is the total length of the road Remember, the question is kilometer, 80 meters to unit Write arithmetic