[obm-l] cara ou coroa?

To: obm-l@xxxxxxxxxxxxxx
Subject: [obm-l] cara ou coroa?
From: Klaus Ferraz <klausferraz@xxxxxxxxxxxx>
Date: Mon, 2 Jan 2006 20:21:49 +0000 (GMT)
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Uma moeda é lançada n vezes. Qual a probabilidade de nao sair 2 caras consecutivas?