Galactic Standard Time

According to the book Mass Effect Revelation the time used in Citadel Space is different to Human Terran Coordinated Universal Time in this way:

A Galactic Standard Day is comprised of 20 hours.

Each Hour is comprised 100 minutes.

Each Minute is comprised of 100 seconds.

Each second is half as long as a human second.

The result is that a tweny hour Galactic Standard Day is 15% longer and a standard 24 hour Terran Coordinated Universal day.