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Question
Find n, if `"n"/(8!) = 3/(6!) + (1!)/(4!)`
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Solution
`"n"/(8!) = 3/(6!) + (1!)/(4!)`
∴ `"n"/(8!) = 3/(6 xx 5 xx 4!) + 1/(4!)`
∴ `"n"/(8 xx 7 xx 6 xx 5 xx 4!) = 1/(4!)[1/10 + 1]`
∴ `"n"/(8 xx 7 xx 6 xx 5) = 11/10`
∴ n = `(8 xx 7 xx 6 xx 5 xx 11)/10`
∴ n = 1848.
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