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If j and k are positive integers, j  2 is divisible by 4 and k  5 is
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12 Nov 2019, 02:06
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64% (02:01) correct 36% (02:32) wrong based on 59 sessions
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If j and k are positive integers, j  2 is divisible by 4 and k  5 is divisible by 4, all of the following could be the value of j  k EXCEPT: A. 43 B. 33 C. 21 D. 13 E. 5 Are You Up For the Challenge: 700 Level Questions
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Re: If j and k are positive integers, j  2 is divisible by 4 and k  5 is
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12 Nov 2019, 03:11
from given info we can say j2k+5/4 jk+3/4 plug in values for jk from given options only option A ; 43 is not divisible IMO A 43 Bunuel wrote: If j and k are positive integers, j  2 is divisible by 4 and k  5 is divisible by 4, all of the following could be the value of j  k EXCEPT: A. 43 B. 33 C. 21 D. 13 E. 5 Are You Up For the Challenge: 700 Level Questions



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Re: If j and k are positive integers, j  2 is divisible by 4 and k  5 is
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12 Nov 2019, 05:51
\(\frac{j  2}{4} \)= m (where m is an integer) and \(\frac{k  5}{4}\) = n (where n is an integer) ==> \(\frac{j  2}{4} \)  \(\frac{k  5}{4}\) = p (where p is an integer) ==> j  k = 4p  3 ==> check the answer choices, and the answer that cannot be expressed in this form is the correct answer
A. 43 B. 33 = 4(9)  3 C. 21 = 4(6)  3 D. 13 = 4(4)  3 E. 5 = 4(2)  3
Therefore, the answer is A.



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Re: If j and k are positive integers, j  2 is divisible by 4 and k  5 is
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12 Nov 2019, 11:13
J=4p+2 K=4q+5 jk = 4(pq)3 Insert values from options. Correct answer after adding 3 to it will be divisible by 4. 4(pq)3=43 ; 46 not divisible by 4 4(pq)3=33 ; 36 divisible by 4 4(pq)3=21 ; 24 divisible by 4 4(pq)3=13 ; 16 divisible by 4 4(pq)3=5 ; 8 divisible by 4
Hence, correct answer choice is A.



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Re: If j and k are positive integers, j  2 is divisible by 4 and k  5 is
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12 Nov 2019, 12:06
j2=4x j=4x+2 k5=4y k=4(y+1)+1 All the options are positive; hence j>k jk= 4(xy1)+1 jk leaves remainder 1, when divided by 4 All options except A leaves remainder 1, when divided by 4. Bunuel wrote: If j and k are positive integers, j  2 is divisible by 4 and k  5 is divisible by 4, all of the following could be the value of j  k EXCEPT: A. 43 B. 33 C. 21 D. 13 E. 5 Are You Up For the Challenge: 700 Level Questions



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Re: If j and k are positive integers, j  2 is divisible by 4 and k  5 is
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20 Nov 2019, 18:52
Bunuel wrote: If j and k are positive integers, j  2 is divisible by 4 and k  5 is divisible by 4, all of the following could be the value of j  k EXCEPT: A. 43 B. 33 C. 21 D. 13 E. 5 Are You Up For the Challenge: 700 Level QuestionsSince j  2 and k  5 are both divisible by 4, their difference is also divisible by 4; that is: j  2  (k  5) = j  k + 3 is divisible by 4. Since j  k + 3 is divisible by 4, then when j  k is divided by 4, it should have a remainder of 1 (notice that if j  k is 1, then j  k + 3 = 4). Therefore, we are looking for the choice that doesn’t yield a remainder of 1 when it is divided by 4, and we see that is the number 43 (all the other choices do indeed yield a remainder of 1 when divided by 4). Answer: A
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Re: If j and k are positive integers, j  2 is divisible by 4 and k  5 is
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24 Nov 2019, 20:10
Solution Given: • j and k are positive integers • j – 2 is divisible by 4 • k – 5 is divisible by 4 To find: • Which cannot be the value of j  k Approach and Working Out: • From the given information we can write,
o \(j – 2 = 4p_1\), where \(p_1\) is an integer
Implies, \(j = 4p_1 + 2\) o Similarly, \(k – 5 = 4p_2\), where, \(p_2\) is an integer
• Thus, \(j – k = 4p_1 + 2 – 4p_2 – 5 = 4(p_1 – p_2) – 3 = 4(p_1 – p_2) – 4 + 1 = 4(p_1 – p_2 – 1) + 1= 4p + 1\) • The only option which is not in the form of 4p + 1 is option A, 43 Hence, the correct answer is Option A. Answer: A
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Re: If j and k are positive integers, j  2 is divisible by 4 and k  5 is
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24 Nov 2019, 20:10






