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Question
Find x if `1/(6!) + 1/(7!) = x/(8!)`
Solution
Given that `1/(6!) + 1/(7!) = x/(8!)`
`1/(6!) + 1/(7*6!) = x/(8*7*6!)`
Cancelling all 6! we get
`1/1 + 1/7 = x/(8 xx 7)`
`(7 + 1)/7 = x/(8 xx 7)`
`8/7 = x/(8 xx 7)`
x = `8/7 xx 7 xx 8` = 64
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