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If K is a positive integer less than 10 and N = 4,321 + K, what is the
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09 Dec 2014, 06:38
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Re: If K is a positive integer less than 10 and N = 4,321 + K, what is the
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09 Dec 2014, 07:33
statement 1 : N is divisible by 3.
N=4321+K sum of digits of N = 4+3+2+1 = 10 so K can be 2,5 or 8 to make N divisible for 3. Not sufficient
statement 2 : N is divisible by 7
N= 4321+K If we divide 4321 by 7, we get remainder of 2. To make N divisible 7, K must be 5, since K is a positive integer less than 10. statement is sufficient.
Ans = B



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Re: If K is a positive integer less than 10 and N = 4,321 + K, what is the
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09 Dec 2014, 09:25
If K is a positive integer less than 10 and N = 4,321 + K, what is the value of K?
(1) N is divisible by 3. Insufficienta number is divisible by 3 if the sum of its digits are divisible by 3. To do so, 4+3+2+1+k must equal a multiple of 3so k must be 2, 5 or 8. (2) N is divisible by 7. Sufficienthere's a cool rule for divisibility by 7multiple the last digit (ones digits) by 2 and subtract from the rest of the numbers. If the resulting number is divisible by 7, the original number is divisible by 7. So, let's just check with 2, 5 and 8. With those n would be 4323, 4326 and 4329. So we would do 432  2*3 = 426 (not div); 432  2*6 = 420 (yes!) and 432  2*9 = 414 (not div). k = 5.
Choice B



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Re: If K is a positive integer less than 10 and N = 4,321 + K, what is the
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23 Feb 2016, 12:53
There's no need to memorize any divisibility rules for 7. Just substract 4200 (which is divisible by 7) and 119 and we get 2+k. So, the only way 2+k is divisible by 7 is if k=5. Answer B
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Re: If K is a positive integer less than 10 and N = 4,321 + K, what is the
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24 Feb 2016, 13:40
intheend14 wrote: If K is a positive integer less than 10 and N = 4,321 + K, what is the value of K?
(1) N is divisible by 3. Insufficienta number is divisible by 3 if the sum of its digits are divisible by 3. To do so, 4+3+2+1+k must equal a multiple of 3so k must be 2, 5 or 8. (2) N is divisible by 7. Sufficienthere's a cool rule for divisibility by 7multiple the last digit (ones digits) by 2 and subtract from the rest of the numbers. If the resulting number is divisible by 7, the original number is divisible by 7. So, let's just check with 2, 5 and 8. With those n would be 4323, 4326 and 4329. So we would do 432  2*3 = 426 (not div); 432  2*6 = 420 (yes!) and 432  2*9 = 414 (not div). k = 5.
Choice B Exactly why did you choose to check with 2 5 and 7...why not 1 3 and 8....or 4 6 and 9........



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Re: If K is a positive integer less than 10 and N = 4,321 + K, what is the
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13 Mar 2016, 23:03



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Re: If K is a positive integer less than 10 and N = 4321 + K,
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20 Dec 2018, 08:47
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Re: If K is a positive integer less than 10 and N = 4321 + K, &nbs
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20 Dec 2018, 08:47






