It's 8 because it's 1/3 of the day. 10/3 is not a nice round number. Also 1/4 of a day is 6 hours, another nice round number! 10/4 is 2.5 which is not as bad a

It's 8 because it's 1/3 of the day. 10/3 is not a nice round number. Also 1/4 of a day is 6 hours, another nice round number! 10/4 is 2.5 which is not as bad as 10/3 but still not a round number.