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nick1816
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nick1816 is there any algebraic way to solve this problem?

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Hi tmevh29, himanshu14, and lnm87,

IF x and y are positive integers and (x−y) = x/y, THEN (x-y) is an integer and x/y logically follows as a positive integer. Hence, (x-y) must be a positive integer, where x-y>0 or x>y.

Let x=K.y, where K is a positive integer greater than 1 (remember that x is a positive integer and x-y>0). Thus,
(x−y) = x/y
(K-1).y = K
y= K/(K-1)

--> K=2, y=2/1=2, y is a positive integer (Yes!)
--> K=3,4,5,... y will NEVER be an integer (NO!).

Therefore, the number of solutions possible for the given equation is 1 only, when y=2 and x=K.y=4.

Final answer is (B)
+1 kudo if this solution enlightens you
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chondro48 Kinshook solutions are perfect. y and y-1 are two consecutive positive integers, and any two consecutive positive integers are co-primes.
Hence; only way y/y-1 is an integer when denominator is equal to 1


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nick1816 is there any algebraic way to solve this problem?

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