The sum of the first $$100$$ positive even whole numbers is $$10100$$.  What is the sum of the first $$101$$ positive even whole numbers? 
Overseas Competition->Knowledge Point->Calculation Modules->Sequences and Number Tables->Arithmetic Sequences
The $$100$$ even numbers that add up to $$10100$$ are $$2$$, $$4$$, $$\cdots $$, $$200$$.  The sum we want is $$2+4+ \cdots + 200 + 202 = 10 100 + 202$$. 