How long is a decade in time?
A decade in time is a period of 10 years.
How long is a decade in minutes?
There are 5,256,000 minutes in a period of 10 years, if you always assumed 365 days a year.
However, you need to look at the decade that you are looking at. If you looked at the period 2000-2009, then 2000, 2004, and 2008 would be leap years. That’s an additional 3 days. The total minutes would therefore be 5,260,320.
If it was 2001-2010, you would have 2 leap days. Total of 5,258,880 minutes.
However, you must also consider that every 400 years there is no leap day on years ending in 00 that begin with a non-multiple of 4, such as the years 1800, 1400, 1000, 600.