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Question
Find the value of n if `1/(8!) + 1/(9!) = "n"/(10!)`
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Solution
`1/(8!) + 1/(9!) = "n"/(10!)`
`1/(8!) + 1/(9 xx 8!) = "n"/(10 xx 9 xx 8!)`
Multiplying thrughout by 8!
`1 + 1/9 = "n"/(10 xx 9)`
`(9 + 1)/9 = "n"/(10 xx 9)`
`"n"/(10 xx 9) = 10/9`
n = `10/9 xx 10 xx 9`
= 100
⇒ n = 100
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