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If n and k are integers whose product is 400, which of the
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30 Jun 2012, 00:46
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57% (01:37) correct 43% (01:25) wrong based on 324 sessions
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If n and k are integers whose product is 400, which of the following statements must be true? A. n + k > 0 B. n is not equal to k. C. Either n or k is a multiple of 10. D. If n is even, then k is odd. E. If n is odd, then k is even.
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Re: If n and k are integers whose product is 400, which of the f
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30 Jun 2012, 02:22
If n and k are integers whose product is 400, whcih of the following statements must be true?Note that the question is: "whcih of the following must be true?" Given: \(nk=400\) For the product of two integers to be even at least one integer must be even. A. n+k>0 > not necessarily true: \(nk=(20)*(20)=400\); B. n does not equal k > not necessarily true: \(nk=20*20=400\); C. Either n or k is a multiple of 10 > not necessarily true: \(nk=16*25=400\). D. If n is even, then k is odd > not necessarily true, \(n\) can be even and \(k\) be even too > \(nk=20*20=400\); E. If n is odd, then k is even > this must be true, if one of the factors is odd (\(n\)) the second one (\(k\)) must be even for their product to be even. Answer: E. Hope it's clear.
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Re: If n and k are integers whose product is 400, which of the
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01 Jul 2012, 20:58
Ohh..this one was really fun..got screwed up btw D and E. Didn't read between the lines. Thanks for explaining Bunuel.
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Re: If n and k are integers whose product is 400, which of the
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05 May 2015, 23:19
Bunuel wrote: If n and k are integers whose product is 400, whcih of the following statements must be true?
Note that the question is: "whcih of the following must be true?"
Given: \(nk=400\)
For the product of two integers to be even at least one integer must be even.
A. n+k>0 > not necessarily true: \(nk=(20)*(20)=400\); B. n does not equal k > not necessarily true: \(nk=20*20=400\); C. Either n or k is a multiple of 10 > not necessarily true: \(nk=16*25=400\). D. If n is even, then k is odd > not necessarily true, \(n\) can be even and \(k\) be even too > \(nk=20*20=400\); E. If n is odd, then k is even > this must be true, if one of the factors is odd (\(n\)) the second one (\(k\)) must be even for their product to be even.
Answer: E.
Hope it's clear. I need just to know that if n is odd, k is even. this is enough to tick e. no need explanation more.



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Re: If n and k are integers whose product is 400, which of the
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12 May 2015, 01:38
Bunuel wrote: If n and k are integers whose product is 400, whcih of the following statements must be true?
Note that the question is: "whcih of the following must be true?"
Given: \(nk=400\)
For the product of two integers to be even at least one integer must be even.
A. n+k>0 > not necessarily true: \(nk=(20)*(20)=400\); B. n does not equal k > not necessarily true: \(nk=20*20=400\); C. Either n or k is a multiple of 10 > not necessarily true: \(nk=16*25=400\). D. If n is even, then k is odd > not necessarily true, \(n\) can be even and \(k\) be even too > \(nk=20*20=400\); E. If n is odd, then k is even > this must be true, if one of the factors is odd (\(n\)) the second one (\(k\)) must be even for their product to be even.
Answer: E.
Hope it's clear. in the test room, we can not find 25x16=400 easily. so, if we see E, if n is odd then k is even tick choice E. that is done.



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Re: If n and k are integers whose product is 400, which of the
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12 May 2015, 03:40
If n and k are integers whose product is 400, which of the following statements must be true?
A.n + k > 0 n and k should have the same sign, but that means that they can also both be negative
B.n is not equal to k. 20 x 20 = 400[i]
C. Either n or k is a multiple of 10. [i]25 x 16 = 400
D. If n is even, then k is odd. k can also be even since even x even will be even E. If n is odd, then k is even. k must be even since odd x even = even



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Re: If n and k are integers whose product is 400, which of the
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17 May 2018, 17:02
Stiv wrote: If n and k are integers whose product is 400, which of the following statements must be true?
A. n + k > 0 B. n is not equal to k. C. Either n or k is a multiple of 10. D. If n is even, then k is odd. E. If n is odd, then k is even. Since an even product must contain at least 1 even number in the multiplication, if n is odd, then k must be even. If you had difficulty differentiating between choices D and E, consider the wording. Choice D states that if we are given that n is even, then k must be odd, which is not necessarily true, because k could be even. Take n = 20 and k = 20 for instance (which also eliminates answer choice B). However, Choice E states that if we are given that n is odd, then k must be even. This is a true statement, because the product nk is even. Answer: E
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Re: If n and k are integers whose product is 400, which of the
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14 Sep 2018, 00:29
we should begin with 400=2^2*5^2*2^2
from this we see that all condition except choice E can be correct but must not be correct.



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Re: If n and k are integers whose product is 400, which of the
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30 Jan 2019, 23:24
Aki wrote: Ohh..this one was really fun..got screwed up btw D and E. Didn't read between the lines. Thanks for explaining Bunuel. Same here. I read D and E as: If one is even, the other is odd. By this logic, I found D and E to be exactly the same



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If n and k are integers whose product is 400, which of the
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31 Jan 2019, 14:19
Hello JeffTargetTestPrep Bunuel
Which is the difference between statements D and E?
Both of them are saying that if one is even, then the second integer should be odd.
D. If n is even, then k is odd. E. If n is odd, then k is even.
(N even)(K odd) = Even When N = 16, K = 25
(K even)(N odd) = Even When K = 16, N = 25



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Re: If n and k are integers whose product is 400, which of the
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04 Feb 2019, 17:50
Stiv wrote: If n and k are integers whose product is 400, which of the following statements must be true?
A. n + k > 0 B. n is not equal to k. C. Either n or k is a multiple of 10. D. If n is even, then k is odd. E. If n is odd, then k is even. Let’s go through the choices. Since n can be 20 and k can be 20, we see that choice A is not true. Since n can be 20 and k can be 20, we see that choice B is not true. Since 400 = 16 x 25, we see that choice C is not true. Since 400 = 20 x 20, we see that choice D is not true. So choice E must be true. We can also show that it must be true because if n is odd, then k must be even, in order to produce an even product (400 is an even number). For example, if n is 25 (odd), then k must be even, which it is, since k must be 16. Answer: E
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Re: If n and k are integers whose product is 400, which of the
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