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Which of the following CANNOT be the sum of two prime intege
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03 Jan 2020, 02:41
03 Jan 2020, 02:41
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Question Stats:
83% (01:08) correct
16% (01:19) wrong based on 6 sessions
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Which of the following CANNOT be the sum of two prime integers?
A. 11
B. 13
C. 19
D. 43
E. 103
A. 11
B. 13
C. 19
D. 43
E. 103
Show: ::
The question has not been posted in the correct format I guess.
Anyways,
as we can see from the options that all options are odd.
Now, 2 is the ONLY even prime.
So, we just have to see the odd integer used to reach the sum as even + odd = odd
1st option = 2+9 = 11
There is our answer as 9 is not a prime integer.
Anyways,
as we can see from the options that all options are odd.
Now, 2 is the ONLY even prime.
So, we just have to see the odd integer used to reach the sum as even + odd = odd
1st option = 2+9 = 11
There is our answer as 9 is not a prime integer.
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Re: Which of the following CANNOT be the sum of two prime intege
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08 Mar 2021, 22:11
08 Mar 2021, 22:11
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Explain the question and get a Kudos!
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Which of the following CANNOT be the sum of two prime intege
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08 Mar 2021, 22:48
08 Mar 2021, 22:48
1
uchihaitachi wrote:
Which of the following CANNOT be the sum of two prime integers?
A. 11
B. 13
C. 19
D. 43
E. 103
A. 11
B. 13
C. 19
D. 43
E. 103
CANNOT be the sum of 2 primes: Subtract 2 from the option choices, if the result can be factorized - then it cannot be expressed as the sum of 2 primes!
A. \(11 - 2 = 9 = (3)(3)\)
B. \(13 - 2 = 11\), cannot factorize
C. \(19 - 2 = 17\), cannot factorize
D. \(43 - 2 = 41\), cannot factorize
E. \(103 - 2 = 101\), cannot factorize
Hence, option E
