system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:How come the 4x100m relay world record (37.10s) gives a faster time than the 100m world record (9.58s) multiplied by 4? This gives each runner an average time of 9.275s, faster than any 100m ever ran. How is this possible?
gpt
The fastest person in the world today is Usain Bolt - he can run 100 meters from a stationary start in 9.58 seconds. He set that time in 2009 and during that race he traveled between the 60 meter and 80 meter markers in 1.61 seconds which is 44.7 km/h or 27.8 mph, the fastest anyone has ever run.

If he was allowed a running start and went on to run the whole race at that speed he would finish in 8.06 seconds. That's 1.52 seconds faster than his standing start record. In real life it's not possible to run quite that fast over the full 100 meters - Usain also holds the record for the fastest electronically recorded time for a 4 x 100 leg at 8.65 seconds.

In a 4 x 100 relay three of the four runners in each team get a running start and have an extra 20 meters to get up to speed before their 100 meters starts. The first 10 meters of that are purely for acceleration, the next ten are for handover within the first runner's 100 meter distance.