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tejal777
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maliyeci
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coelholds
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Guys OA is C.Could somebody please explain?
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maliyeci
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I don't think the answer is C. I think the OA is wrong.
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Sunchaser20
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Initially have chosen A as well, but... on the second thought it's really C:
\(x!+\frac{x}{z}=y\)
\(x*((x-1)!+\frac{1}{z})=y\)

\(x*(\frac{(x-1)!*z+1}{z})=y\)

z can be any integer, provided x=z, which makes St1 insufficient, we need St2.
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No. z can not be any integer.

Based on the equation you found; if x = z then equation becomes (x! + 1). But x can only be the factor of y when the value of x = 1, z=1 and y=2. In other values of x; x can not be a factor of y because x! and x!+1 are coprimes (numbers that do not have any divisors other than 1). So z becomes 1 ;) We can find z.
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maliyeci
No. z can not be any integer.

Based on the equation you found; if x = z then equation becomes (x! + 1). But x can only be the factor of y when the value of x = 1, z=1 and y=2. In other values of x; x can not be a factor of y because x! and x!+1 are coprimes (numbers that do not have any divisors other than 1). So z becomes 1 ;) We can find z.
Agree with you. Have totally missed the condition that x is a factory of y.



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