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If N > 4 and N is a prime number, then what is the remainder when N
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17 Aug 2018, 02:43
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If N > 4 and N is a prime number, then what is the remainder when N
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17 Aug 2018, 03:01
Bunuel wrote: If N > 4 and N is a prime number, then what is the remainder when N^2 is divided by 6?
(A) 0 (B) 1 (C) 2 (D) 3 (E) 4 OA: B As \(N\) can be any prime number such that \(N>4\) , Taking \(N =5\) and squaring it, we get \(N^2=25.\) \(\frac{25}{6}\) will leave \(1\) as remainder.
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If N > 4 and N is a prime number, then what is the remainder when N
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17 Aug 2018, 04:53
All Prime numbers greater than 3 can be expressed in the form of 6k+1 or 6k1 , where k is a not negative integer.
Let N = 6k+1 N^2 = (6k+1)^2 = 36K^2 + 12K + 1 = 12(3K^2 + K) +1
Since 12(3K^2+K) is exactly divisible by 12 , therefore N^2 when divided by 12 leaves a remainder as 1.
B is the answer
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If N > 4 and N is a prime number, then what is the remainder when N
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17 Aug 2018, 05:30
Bunuel wrote: If N > 4 and N is a prime number, then what is the remainder when N^2 is divided by 6?
(A) 0 (B) 1 (C) 2 (D) 3 (E) 4 Smart Question: It can be looked ta in two ways 1) By Properties of Prime numbers Every prime number greater than 3 when divided by 6 leaves remainder either +1 or 1i.e. N^2 divided by 6 will eave remainder ( +1)^2 i.e. +1 hence Answer: option B 2) Take a value of a few prime numbers greater than 4i.e. N may be 5, 7, 11, 13, ... etc i.e. N^2 may be 25, 49, 121, 169, ... etc Dividing each of these values of N^2 by 6 leaves remainder 1 hence Answer: option B
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Re: If N > 4 and N is a prime number, then what is the remainder when N
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17 Aug 2018, 07:28
Bunuel wrote: If N > 4 and N is a prime number, then what is the remainder when N^2 is divided by 6?
(A) 0 (B) 1 (C) 2 (D) 3 (E) 4 Possible Values of \(N = { 5, 7 , 11 , 13..............}\) Try with the possible values of \(\frac{N^2}{6}\) , in each case answer must be 1, Thus answer must be (B) 1
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Re: If N > 4 and N is a prime number, then what is the remainder when N
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17 Aug 2018, 08:15
Bunuel wrote: If N > 4 and N is a prime number, then what is the remainder when N^2 is divided by 6?
(A) 0 (B) 1 (C) 2 (D) 3 (E) 4 I think the easiest way to solve this qs is number plugging. Since we can't have 2 correct answers at the same time, we just need to pick a number and see which answer choice matches the result. In this case let N=5 > \(N^2\) = 25 > remainder when 25 is divided by 6 is 1. Answer B.
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Re: If N > 4 and N is a prime number, then what is the remainder when N
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18 Aug 2018, 09:39
if N = 5 then N^2 = 25 25/6 remainder is 1 So Answer is B
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Re: If N > 4 and N is a prime number, then what is the remainder when N
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18 Aug 2018, 16:46
Bunuel wrote: If N > 4 and N is a prime number, then what is the remainder when N^2 is divided by 6?
(A) 0 (B) 1 (C) 2 (D) 3 (E) 4 we can plug numbers for N. It's given that N is prime greater than 4. So, N can be : 5, 7 , 11. \(\frac{(5)^2}{6}= 24 + 1\) \(\frac{(7)^2}{6}= 48 + 1\) So, in all case we will have a remainder 1. The best answer is B.



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Re: If N > 4 and N is a prime number, then what is the remainder when N
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20 Aug 2018, 11:20
Bunuel wrote: If N > 4 and N is a prime number, then what is the remainder when N^2 is divided by 6?
(A) 0 (B) 1 (C) 2 (D) 3 (E) 4 We can let N = 5, so N^2 = 25, and we have: 25/6 = 4 remainder 1 Answer: B
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