Xiao Yun sits at the window of the train. The train runs from the south end of the bridge to the north end. Xiao Yun measures that the time of sharing is 80 seconds. His mother asks Xiao Yun how long the bridge is, so ↓ Then above: Xiaoyun immediately clocks from a certain pole beside the railway, and it takes 25 seconds to reach the 10th pole. If the distance between each two poles is 50 meters, Xiaoyun can calculate the length of the bridge. Then, how long is the bridge?

Xiao Yun sits at the window of the train. The train runs from the south end of the bridge to the north end. Xiao Yun measures that the time of sharing is 80 seconds. His mother asks Xiao Yun how long the bridge is, so ↓ Then above: Xiaoyun immediately clocks from a certain pole beside the railway, and it takes 25 seconds to reach the 10th pole. If the distance between each two poles is 50 meters, Xiaoyun can calculate the length of the bridge. Then, how long is the bridge?

9 * 50 = 450m, so the length of the bridge is 450 * (80 / 25) = 1440m

The two trains are running in opposite directions. The express train is 200m and the local train is 160m. From the local train, it takes 10 seconds for the express train to pass the window. From the express train, it takes 10 seconds for the local train to pass the window
How many seconds?
A、12 B、10 C、8 D、6

The speed sum is: 200 △ 10 = 20 m / s
From the fast train, it takes 160 △ 20 = 8 seconds for the slow train to pass the window
Select C, 8

The length of the fast and slow trains are 150 meters and 200 meters respectively. They run on parallel tracks. If it takes 6 seconds for people on the slow train to see the fast train passing the window, what is the time for people on the fast train to see the slow train passing the window______ Seconds

Suppose that it takes x seconds for a person on an express train to see the slow train passing through the window. 1506 = 200X, the solution is x = 8. It is tested that x = 8 is the solution of the original fractional equation, so the answer is 8