Lets convert everything into m/s to make it easier. 25km/h = 6.9444... or 125/18 meters per second. He travels for x amount of seconds.alberto finishes the remainder of the race at an average of 25 km/h
27.5km/h = 7.638888.... or 275/36 meters per second. He trevels for x amount of seconds to catch up, minus 12 minutes (720 seconds) of travel time.lance averages 27.5 km/h after starting up again
This is only a single variable question.
Solve for x, which is the time travelled in seconds after lance crashes. Then add on the extra hour (3600 seconds) and you will have your total time after the start of when lance will catch up.