(a) Determine the average of the integers . (b) Suppose that are five consecutive integers. (i) Determine a simplified expression for the sum of these five consecutive integers. (ii) If the average of these five consecutive integers is an odd integer, explain why must be an odd integer. (c) Six consecutive integers can be represented by , where is an integer. Explain why the average of six consecutive integers is never an integer.
, 2010
Want a route through all this instead of an archive? The track
puts 2,604 problems in a working order, from Junior Challenge level to the IMO shortlist.