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**SuperCalculus** So yeah, basically I got my GCSE Maths result back, and I only dropped one mark, but I'm not sure how or where I lost it. I'll post my method, and then you guys can tell me what I did wrong.

Question: Prove that the sum of two consecutive odd integers is always even.

My method;

Let two consecutive odd integers be $\displaystyle x$ and $\displaystyle x + 2$.

Hence, $\displaystyle x + (x + 2) = Even?$

$\displaystyle 2x + 2 = Even$

Since twice anything is always even;

$\displaystyle Even + even = even$, which is true. Therefore, the sum of two consecutive odd integers is always even. Any idea where I dropped the mark? I only got two of a possible three.