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Question
Find x in each of the following:
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Solution
\[ \frac{x}{10!} = \frac{1}{8!} + \frac{1}{9!}\]
\[ \Rightarrow \frac{x}{10!} = \frac{1}{8!} + \frac{1}{9(8!)}\]
\[ \Rightarrow \frac{x}{10!} = \frac{9 + 1}{9(8!)} \]
\[ \Rightarrow \frac{x}{10!} = \frac{10}{9!}\]
\[ \Rightarrow \frac{x}{10 \times 9!} = \frac{10}{9!}\]
\[ \Rightarrow x = 100\]
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