What is the arithmetic mean of and ?
If the average of the above numbers is 13, what is ?
What is the arithmetic mean of all the prime numbers less than 20?
What is the arithmetic mean of all the leap years in the century?
Details and Assumptions:
A year that is divisible by 4 is a leap year. However, a year that is divisible by 100 but not by 400 is a common year.
The begins with January 1, 1801 and ends with December 31, 1900.
What is the arithmetic mean of the above sequence?