When the train passes a bridge, Xiao Ming sits by the window. It takes 80 seconds to measure from his seat. His father asks Xiao Ming how long the bridge is. Xiao Ming starts to count the time from a certain pole beside the railway, and it takes 25 seconds for the tenth pole. If the distance between each two poles beside the railway is 50 meters, please help Xiao Ming calculate how long the bridge is

When the train passes a bridge, Xiao Ming sits by the window. It takes 80 seconds to measure from his seat. His father asks Xiao Ming how long the bridge is. Xiao Ming starts to count the time from a certain pole beside the railway, and it takes 25 seconds for the tenth pole. If the distance between each two poles beside the railway is 50 meters, please help Xiao Ming calculate how long the bridge is


50 × (10-1) △ 25 × 80, = 450 × 25 × 80, = 1440 (m); answer: the length of the bridge is 1440 M