Evaluate: $102^2 - 98^2$
This problem involves two squares of numbers that are close to each other, so I can use the difference of squares formula: $(a^2 - b^2) = (a+b)(a-b)$. In this case, $a = 102$ and $b = 98$, so I can rewrite the expression as $(102+98)(102-98)$. This simplifies to $(200)(4)$, which is easy to multiply. I get $800$ as the final answer. 