Question 987291
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We have 8 tiles taken 5 at a time, and order is important:
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n=total number of tiles, x=number chosen at a time
{{{nPx=n!/(n-x)!}}} 
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{{{8P5=8!/(8-5)!}}}
{{{8P5=8!/3!}}}={{{8*7*6*5*4=6720}}}
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ANSWER: There are 6720 possible arrangements.