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\centerline{Mathematics 351 -- Abstract Algebra 1}
\centerline{Solutions for Problem Set 9}
\centerline{November 9, 2007}
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{\it Section 7.5}
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5.  (a)  ${\mathbb Z}_{24}$ has order 24, so by Lagrange's
Theorem, the possible orders of subgroups of ${\mathbb Z}_{24}$ are 
$1,2,3,4,6,8,12,24$.  
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