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Question
Find x in each of the following:
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Solution
\[ \frac{1}{4!} + \frac{1}{5!} = \frac{x}{6!}\]
\[ \Rightarrow \frac{1}{4!} + \frac{1}{5(4!)} = \frac{x}{6!}\]
\[ \Rightarrow \frac{5 + 1}{5(4!)} = \frac{x}{6!}\]
\[ \Rightarrow \frac{6}{5!} = \frac{x}{6!}\]
\[ \Rightarrow \frac{6}{5!} = \frac{x}{6 \times 5!}\]
\[ \Rightarrow x = 36\]
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