Consecutive Integers

Question 1

What is the formula to count the number of consecutive integers in an inclusive range?

Answer 1

(Last - First + 1)

Question 2

What is the formula to calculate the sum of consecutive integers in an inclusive range?

Answer 2

Average x Number of Terms

Question 3

What is the formula to calculate the average of an evenly-spaced set?

Answer 3

(First number + Last number) / 2