Problem
First name
Dominique
School
Furness Academy
Country
Age
0
Three consecutive numbers:
12 = n-1
13 = n
14 = n+1
This is the same as 3n, because the number that is one higher than the original number adds one on to the number that is one lower than the original number. If you took one away from 14 and added it back onto 12, all three of the numbers with equal 13.
Conclusion: 3 consecutive numbers added together will ALWAYS equal a multiple of 3.