Leaping up the Obelisk

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Leaping up the Obelisk

An obelisk has no more than 100 stairs. If I go up the stairs two at a time, there will be one step left over at the top. If I go up the stairs three at a time, there will be two left at the top. If I go up the stairs seven at a time, there will be six stairs left over at the top. What is the maximum number of stairs the obelisk could have?

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Problem by BogusBoy

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