I have question here which has puzelled me since monday. Hope there is somebody here who can give a hint/help.(adsbygoogle = window.adsbygoogle || []).push({});

Let "a" be number written in base 10.

a_0 * 10^0 + a_1 * 10^1 + a_2 * 10^2 + -------+ a_n * 10^n

where 0 \leq a_i \leq 10.

Prove that the number 2 divides a, if and only if 2 divides a_0.

Can anybody give me a hint on how to go about solving this?

Can I claim that a_0 must not equal zero for 2 to divide a_0 ??

Sincerley Yours

Fred

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# Homework Help: Urgend: Sum of digits question

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