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Question
Find x in each of the following:
Solution
\[\frac{1}{6!} + \frac{1}{7!} = \frac{x}{8!}\]
\[ \Rightarrow \frac{1}{6!} + \frac{1}{7(6!)} = \frac{x}{8!}\]
\[ \Rightarrow \frac{7 + 1}{7(6!)} = \frac{x}{8!}\]
\[ \Rightarrow \frac{8}{7!} = \frac{x}{8!}\]
\[ \Rightarrow \frac{8}{7!} = \frac{x}{8 \times 7!}\]
\[ \Rightarrow x = 64\]
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