<PRE><B>Question 1073432</B>
Note that arrangements are permutations
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(1.a)  4! * 5! * 2! = 24 * 120 * 2 = 5760 possible arrangements
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consider the math books and science books as two distinct entities, then you have 2! ways to arrange those two entities
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(1.b) arrange the science books first, we have
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5 m 4 m 3 m 2 m 1
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next arrange the math books
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5 4 4 3 3 2 2 1 1 = 2880 possible arrangements
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