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If j and k are integers and j^2/k is odd, which of the following must
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10 Jan 2011, 12:54
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If j and k are integers and j^2/k is odd, which of the following must be true ? (A) j and k are both even (B) j = k (C) If j is even, k is even (D) j is divisible by k (E) j^2 > k
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Re: If j and k are integers and j^2/k is odd, which of the following must
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10 Jan 2011, 13:05
rxs0005 wrote: If j and k are integers and j^2 / k is odd,
which of the following must be true ?
(A) j and k are both even (B) j = k (C) If j is even, k is even (D) j is divisible by k (E) j^2 > k If j and k are integers and j^2 / k is odd, which of the following must be true ? Given: \(j\) and \(k\) are integers and \(\frac{j^2}{k}=odd\) > \(j^2=k*odd\) (A) j and k are both even: not necessarily true, for example \(j=1\) and \(k=1\); (B) j = k: not necessarily true, for example \(j=3\) and \(k=1\); (C) If j is even, k is even: as \(j^2=k*odd\) then in order \(j\) to be even \(k\) must be even too, so this statement must be true; (D) j is divisible by k: not necessarily true, for example \(j=3\) and \(k=9\); (E) j^2 > k: not necessarily true, for example \(j=1\) and \(k=1\). Answer: C.
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If j and k are integers and j^2/k is odd, which of the
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Updated on: 14 Jul 2016, 19:33
If j and k are integers and \(\frac{{j^2}}{k}\) is odd, which of the following must be true? (A) j and k are both even (B) j = k (C) If j is even, k is even (D) j is divisible by k (E) \(j^2\) > k What's the best way to approach these questions? Picking numbers or anything else?
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Re: If j and k are integers and j^2/k is odd, which of the following must
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10 Jan 2011, 18:43
rxs0005 wrote: If j and k are integers and j^2 / k is odd,
which of the following must be true ?
(A) j and k are both even (B) j = k (C) If j is even, k is even (D) j is divisible by k (E) j^2 > k Think that if \(j^2/k =\) Odd Integer then j^2 is divisible by k. Also either both of them are odd or both j and k are even. It is not possible that one of them is odd and one of them is even. Why? If j is even and k is odd, j^2/k is even since j^2 will retain its 2s. If k is even and j is odd, j^2/k is not an integer because an odd number is never divisible by an even number. So if j is even, k has to be even.
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Re: If j and k are integers and j^2/k is odd, which of the
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25 Feb 2012, 03:56
If j and k are integers and j^2 / k is odd, which of the following must be true ? Actually you can use mixed approach. Given: \(j\) and \(k\) are integers and \(\frac{j^2}{k}=odd\) > \(j^2=k*odd\) (A) j and k are both even: not necessarily true, for example \(j=1\) and \(k=1\); (B) j = k: not necessarily true, for example \(j=3\) and \(k=1\); (C) If j is even, k is even: as \(j^2=k*odd\) then in order \(j\) to be even \(k\) must be even too, so this statement must be true; (D) j is divisible by k: not necessarily true, for example \(j=3\) and \(k=9\); (E) j^2 > k: not necessarily true, for example \(j=1\) and \(k=1\). Answer: C.
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Re: If j and k are integers and j^2/k is odd, which of the
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14 Jul 2016, 12:22
Bunuel wrote: If j and k are integers and j^2 / k is odd, which of the following must be true ?
Actually you can use mixed approach.
Given: \(j\) and \(k\) are integers and \(\frac{j^2}{k}=odd\) > \(j^2=k*odd\)
(A) j and k are both even: not necessarily true, for example \(j=1\) and \(k=1\);
(B) j = k: not necessarily true, for example \(j=3\) and \(k=1\);
(C) If j is even, k is even: as \(j^2=k*odd\) then in order \(j\) to be even \(k\) must be even too, so this statement must be true;
(D) j is divisible by k: not necessarily true, for example \(j=3\) and \(k=9\);
(E) j^2 > k: not necessarily true, for example \(j=1\) and \(k=1\).
Answer: C. Hi Bunuel, please change format of the question, when I saw the question, I thought J to the power of 2/K and started to solve. When I saw your solution, then I realized that I read the question in different way.Such typing mistakes must be avoided.



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Re: If j and k are integers and j^2/k is odd, which of the
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14 Jul 2016, 20:22
msk0657 wrote: Bunuel wrote: If j and k are integers and j^2 / k is odd, which of the following must be true ?
Actually you can use mixed approach.
Given: \(j\) and \(k\) are integers and \(\frac{j^2}{k}=odd\) > \(j^2=k*odd\)
(A) j and k are both even: not necessarily true, for example \(j=1\) and \(k=1\);
(B) j = k: not necessarily true, for example \(j=3\) and \(k=1\);
(C) If j is even, k is even: as \(j^2=k*odd\) then in order \(j\) to be even \(k\) must be even too, so this statement must be true;
(D) j is divisible by k: not necessarily true, for example \(j=3\) and \(k=9\);
(E) j^2 > k: not necessarily true, for example \(j=1\) and \(k=1\).
Answer: C. Hi Bunuel, please change format of the question, when I saw the question, I thought J to the power of 2/K and started to solve. When I saw your solution, then I realized that I read the question in different way.Such typing mistakes must be avoided. j^2/k mathematically can only mean j^2 divided by k. If it were j to the power of k/2 it would be written as j^(2/k).
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Re: If j and k are integers and j^2/k is odd, which of the following must
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17 Oct 2017, 10:56
rxs0005 wrote: If j and k are integers and j^2/k is odd, which of the following must be true ?
(A) j and k are both even (B) j = k (C) If j is even, k is even (D) j is divisible by k (E) j^2 > k Let’s check each answer choice using numbers. (A) j and k are both even Let’s say j = 3 and k = 1: we have 3^2/1 = 9, but neither j nor k is even. So, A is not the answer. (B) j = k Let’s say j = 3 and k = 1: we have 3^2/1 = 9, but j is not equal to k. So, B is not the answer. (C) If j is even, k is even This is an “ifthen” statement. The only way this is false is if we can find an even number j and an odd number k and still have j^2/k = odd. However, if j is even, then j^2 is even. If j^2 is even and k is odd, and if j^2 is divisible by k, then j^2/k must be even since even/odd can’t ever be odd. So, we can’t find any even number j and odd number k such that j^2/k = odd, and thus C must be the correct answer. However, let’s also check why the last two answer choices can’t be correct. (D) j is divisible by k Let’s say j = 2 and k = 4: we have 2^2/4 = 1, but j is not divisible by k. So, D is not the answer. (E) j^2 > k Let’s say j = 1 and k = 1: we have 1^2/1 = 1, but j^2 is not greater than k. So, E is not the answer. Answer: C
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Re: If j and k are integers and j2 k is odd, which of the following must b
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03 Nov 2017, 05:06
nkmungila wrote: If j and k are integers and \(\frac{j^2}{k}\) is odd, which of the following must be true?
A. j and k are both even B. j = k C. j is divisible by k D. If j is even, k is even E. \(j ^2 > k\) Hi... You can easily find others NOT to be true in all cases.. But D says.. if j is even, k is even... Say j is odd but k is even j^2/k would not be an integer itself.. So this must be TRUE D
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Re: If j and k are integers and j^2/k is odd, which of the following must
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06 Nov 2017, 16:22
rxs0005 wrote: If j and k are integers and j^2/k is odd, which of the following must be true ?
(A) j and k are both even (B) j = k (C) If j is even, k is even (D) j is divisible by k (E) j^2 > k The only way to obtain an odd quotient is if either of these two cases occurs: 1) both numerator and denominator are odd, such as 9/3 = 3, or 2) both numerator and denominator are even, such as 6/2 = 3. Secondly, if an integer is odd, its square is also odd, and if an integer is even, its square is even. Since j^2/k is odd, we see that if j itself is odd, then j^2 is odd, and so k must be odd. OR, if j is even, then j^2 is even, and k must be even. Thus, of the answer choices, only D must be true. Answer: D
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Re: If j and k are integers and j^2/k is odd, which of the following must
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