If the sum of $$9$$ consecutive odd integers is $$1935$$, what is the sum of the next $$9$$ consecutive odd integers? 
Overseas Competition->Knowledge Point->Counting Modules->Permutations and Combinations->Combinations
Each number in the second sum is $$18$$ greater than the corresponding number in the first sum. Thus the second sum is $$1935 +18 \times9 = 2097$$. 