If x and y are positive integers, is (x/y)^z > 1 ?
(1) x - y = -5
(2) z ≠0
The OA is E.
Both statements are not sufficient? Why? How can I conclude that the correct option is E?
If x and y are positive integers, is (x/y)^z > 1 ?
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Statement 1: x - y = -5Vincen wrote:If x and y are positive integers, is (x/y)^z > 1 ?
(1) x - y = -5
(2) z ≠0
The OA is E.
Both statements are not sufficient? Why? How can I conclude that the correct option is E?
=> A positive integer (y) is subtracted from a positive integer (x), leaving a negative integer (-5); thus, y > x.
Thus, x/y < 1
Case 1: If z is negative. Say z = -1, x = 1 and y = 6, then (x/y)^z = (1/6)^(-1) = 6 > 1. The asnwer is Yes.
Case 2: If z is positive. Say z = 1, x = 1 and y = 6, then (x/y)^z = (1/6)^(1) = 1/6 < 1. The asnwer is No.
No unique answer. Insufficient.
Statement 2: z ≠0
Both the cases discussed above are applicable here too. Insufficient.
Statement 1 & 2:
As stated, both the cases discussed above are applicable here too. Insufficient.
The correct answer: E
Hope this helps!
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