Well if each round is 3 minutes long, and they have a 1 minute rest period between each round, the answer is 27 minutes.
They box for 21 minutes, and they rest after each round from 1 to 6, and that is why the answer comes out to 27 minutes.
3 minutes
3 MINUTES FOR THE PROS
39
There are four rounds that last two minutes each in an Olympic boxing match.
Each boxing round is 3 minutes, so that would be 36 minutes of fighting.
Each boxing round is 3 minutes, so that's 36 minute of fighting
3 minutes per round, 36 minutes
Currently an Olympic boxing match consists of four rounds and each round lasts for two minutes. In the past, boxing matches were made up of 3 rounds each of which lasted for three minutes.