Mais um desafio !!
Autor: Alemães na Matemática | Publicado: 2011-02-23T09:26:00-08:00

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 <![endif]-->  Deseja-se descobrir quantos degraus são visíveis numa escada rolante. Para isso foi feito o seguinte: duas pessoas começaram a subir a escada juntas, uma subindo um degrau de cada vez enquanto que a outra subia dois . Ao chegar ao topo, o primeiro contou 21 degraus enquanto o outro 28. Com esses dados foi possível responder a questão. Quantos degraus são visíveis nessa escada rolante? (obs: a escada está andando).
http://www.somatematica.com.br/desafios.php
Postado por: Danilo&nbsp; 8° ano