What is the difference in time between crossing a bridge that is 2,737 meters long at an average speed of 322 meters per minute and in crossing the same bridge at an average speed of 80 meters per minute?

so the bridge is 2737 meters long.

at a speed of 322 m/min, meaning for for every passing minute, there are 322 meters covered, so we can simply divide 2737/322 to get a "minute" amount, namely 8.5, at 322 m/min, it takes 8.5 minutes to cross it.

now, if we instead are going slower, at 80 m/min, 80 meters to a minute, then it'll be 2737/80 minutes, namely 34.2125.

their time difference is 34.2125 - 8.5  = 25.7125 minutes, so about 25 minutes and 43 seconds.

people went from manufacturing one object at a time by hand to manufacturing many objects in factories