# How can i prove the following? [duplicate]

I want to prove that if $5\mid(a+11)$ and $5\mid(16-b)$ then $5\mid(a+b)$

Can you help me?

Thanks in advance PS. It's urgent!

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## marked as duplicate by amWhy, Douglas S. Stones, Math Gems, Jasper Loy, MikeApr 2 '13 at 18:17

Hint: $$a + b = (a + 11) - (16 - b) + 5$$